Tunabelly Software

TG Pro Tutorial

Temperature monitoring, fan control & diagnostics for all Mac models

Extend the life of your Mac with TG Pro, whether you have an older one or brand a new MacBookPro. It supports all models from 2008 right up to the newest 2019 ones.

Quickly view CPU, GPU, logic board or hard drive temperatures, check battery health and the other hardware diagnostics. If it's getting hot, manually boost the fan speeds, or allow TG Pro to do it automatically to help keep the Mac cool and running fast. Get local or email notifications for temperature events along with full logging for further analysis.

This tutorial will guide through all the features and options of TG Pro 2.46 and higher. If you don't have a copy yet, download it for free now. All features are available with the free download with the exception of the hardware diagnostics.

Save 50% off TG Pro for a limited time!


Getting started

Open up TG Pro and the first thing you'll notice is the main window with a whole bunch of temperatures, fan speeds and diagnostics.

This is one of the main areas of the app that you'll interact with. This will be explained in more detail in the following sections.
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The other main area to check out to see everything quickly, is the status menu. It's very similar to the main window except it's in a more compact form.

The status menu is available by clicking on the TG Pro icon located in the top right of the menu bar. It will look similar to the following, depending on your preferences:
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To adjust some of the common settings, open up the Preferences (either from the application menu, or the menu bar icon) and choose the Application tab. It will look like this:
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Here's what each one is for:

Login - To have the app started automatically when starting or logging into your Mac, check the "Automatically launch TG Pro" checkbox.

Run Mode - To have the app run in the background with no dock icon or menu bar, choose "Background". This is the most common setting since it allows the app to run in the background and still provide the status menu (and from there the main window as well).

Update Frequency - This is how often TG Pro checks temperatures and fan speeds. The default is 10 seconds and is usually a good compromise between continuous updates and not querying too often.

HotKeys - If you'd like to be able to press a keyboard combination to show the main window, check the checkbox for the one you'd like then click the "Record shortcut" button. Then press the keyboard combination you'd like. For example, it could be something like Shift-Control-F or Shift-Command-Option-M, and so on.

Console Output - This is for debugging purposes and you generally not be checked unless requested to do so by Tunabelly support.

Hackintosh - Use this option to enable the generic sensor mode which will dynamically determine which sensors are available instead of by Mac model. This is very useful for Hackintosh models (homemade Macs) since they need a valid Mac model name, but don't always have the proper sensor list to match it.

Reset app to defaults - Completely reset the app back to its original state. This will reset all Auto Boost rules and preferences. Read more about it here.
To change how the information is displayed in the menubar, switch to the MenuBar preference tab. Here's what it looks like:
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Menu Bar Content- Choose which temperatures are displayed along with optional fan speeds.

Stacking Order - Decide which way the information will be stacked. Horizontal will use more space and have a larger font, whereas vertical will use less space and have a smaller font. Here's an example of what each one looks like:


Screen Shot 2017-04-26 at 11.53.32 AM


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Options - A few choices to customize how the information will be displayed. Note: The "Use smaller font" is not available for the Vertical stacking order since it already uses a fairly small font.
Another few settings that are worth checking out before continuing are in the Temperature preference tab. It will look like this:
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Temperature Unit - Choose between displaying either Celsius (C) or Fahrenheit (F).

Optional - Enable this to also check the drive temperatures through S.M.A.R.T. On some older Macs this can slow things down which is why there is a warning about this.

Reset Max Temperatures - Reset all the maximum temperatures that have been recorded. These are shown in the main window when hovering the mouse over a particular temperature as well as a vertical black bar at the end of each row.

Monitor all internal temperatures

One of the most common thing people like to do with TG Pro is to check and monitor all the internal temperatures. Sometimes it's just for curiosity, and sometimes it's because there might be an issue and this will help to track it down.

The best place to start is the main window to look at all the different temperatures sensors, and which types are available.
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On the left (#1) is a list of hardware areas along with a row at the top labelled "All". Choosing this as in the screenshot above will show every temperature sensor that TG Pro can detect. If you'd like to only see sensors for a particular area (ex: CPU), just click once on that row.

On the right (#2), are all the temperature sensors for the chosen area. For each sensor, you'll see the name, the current temperature and a bar showing where the temperature is between 0°C to 105°C (32°F to 221°F).

Viewing maximum temperature values

To see the maximum recorded temperature for a particular sensor, simply hover the mouse over that row and a popover will appear. The same information is displayed as the vertical line at the end of each temperature level.

Note that the popover will not appear if the update frequency is set to lower than around 4 seconds. This is because macOS waits a few seconds when hovering the mouse before displaying a tooltip/popover. If the update frequency is set for example to the lowest, which is 1 second, there is not enough of a delay before the table (with all the temperature values) refreshes.

To change this, open the app preferences, click the Application tab and move the Update Frequency slider to the right at least to between the 1 and 10 second markers.
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To reset the maximum temperature markers, click the gear icon in the top right of the main window and choose "Reset Max Temperatures" from the contextual menu that appears.
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What do green, yellow and red mean for temperatures?

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The temperature bars will be one of three colours:

Green - The temperature is between 0 to 89C (32 to 192F) and is generally nothing to worry about.

Orange - The temperature is between 90 to 99C (194 to 210F) and is getting closer to the thermal limit of the hardware.

Red - The temperature is at or above 100C (212F) and it very close to the thermal limit. It's a good rule to not let components run this hot for an extended period of time. It's usually a CPU sensor that will display a temperature this high. Most of the Intel CPUs have a maximum of 95C (203F) to 105C (221F) at which point they will slow down to avoid damage.

If you find components are continuously showing orange or red, and the fans are not running at full speed, please see the section on using fan control to cool down the Mac.

Different types of sensors

Each Mac has a unique set of temperature sensors that TG Pro can access. However, some are common across all models, such as CPU, Memory, etc. Here are the different types that might be available along with an explanation of what they are.
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CPU - Sensors inside the CPU (Central Processing Unit). These are the ones that usually get quite hot since it's the CPU that does most of the work to make the computer function.
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CPU Relative - Available on some Macs with Intel Xeon CPUs, which at the time of this writing is only the Mac Pro. These are special sensors that manage the ProcHot temperature. ProcHot is interesting because it's actually the reverse of a normal temperature. It starts at a negative number and increases as the temperature goes up. When it reaches 0, the CPU will begin to throttle to cool it down.
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GPU - Sensors inside the GPU (Graphics Processing Unit). These can be for either an integrated graphics chip (ex: Intel Iris) or for a discrete card (ex: AMD Radeon R9). Note that only GPUs that are part of the main motherboard will be shown, which means that PCIe cards in a Mac Pro will not be included.
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Battery - Available on MacBooks and MacBook Pros since they are the only models to have a battery.
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Enclosure - Available on some desktop Mac models where there are temperature sensors inside the case although not on any particular component. This also includes the HD drive bays for the older model Mac Pros.
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HD - Temperatures from the hard drives from either S.M.A.R.T. or if the model has built-in sensors.
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LCD - Temperatures from the LCD screen on certain iMac models.
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Memory - Temperatures from the memory slots, banks or in some models memory that has been soldered to the motherboard.
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Logic Board - Temperatures from the logic board which contains controllers that connect the disparate components of the computer together.
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Northbridge - Chip on the logic board that integrates the CPU, memory and PCIe expansion. For more information, please see here.
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Optical - Temperatures from around the built-in optical (CD or DVD) drive in some older iMac models.
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PCI - Temperatures from around the PCI/PCIe slots in some older Mac Pro models.
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Palm Rest - Temperatures from around the trackpad / palm rest on some MacBook and MacBook Pro models.
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Power - Temperatures from around the power supply, or power adapter in some MacBook and MacBook Pro models.
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Thunderbolt - Temperatures from around the Thunderbolt port(s).
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Wireless - Temperatures from around the Airport (wireless) chip.

Monitor fan speeds

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Going back to the main window, let's look at the Fans area, as indicated by #1.

Each fan that's inside the Mac will be shown in this area. In this example (a Late 2013 13" MacBook Pro), there is only one fan. The fan speeds are shown as RPM, which stands for Revolutions Per Minute. So if the fan is spinning at 2000 RPM that means it does a full spin 2000 times per minute. The higher the RPM the faster the fan is spinning which equates to more cooling. If you're interested in learning more about how the fans work, check out the Wikipedia article on Computer fans.

#2 shows the name of the fan, which is this case is "Right Side" since that's its physical location. It also shows the current speed, which is 1935 RPM.

#3 shows the minimum speed of the fan, which is 1280 RPM. The fan speed will never go below this, although you may see a slight variation occasionally where it's a few RPM lower. In this case it might dip to 1275 RPM when the fan speeds are changing and then settle at 1280 RPM.

#4 shows the maximum speed of the fan, which in this example is 6199 RPM. The fan speed will never go above this, although the same caveat as in #3 applies.

#5 is for quickly changing the fan control mode. This is detailed in the Using fan control to cool down the Mac section.
Note: On some Macs, such as the 2015-2017 MacBook Pro 13" models (MacBookPro12,1, MacBookPro13,1, MacBookPro13,2 and MacBookPro14,1), the hardware has the ability to turn the fan off when the CPU is under a light load. When this happens, TG Pro cannot control it until the hardware turns it back on. This is what it will look like:
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What do green, yellow and red mean for fan speeds?

Just like the temperature bars a few sections above, they will be one of three colours:

Green - The fan speed is between 0-74% of the maximum. For example, if it was 50% the green slider would be exactly half way between the minimum and maximum speeds. This is generally nothing to worry about since the system will move the fan speeds up and down as necessary, although usually quite conservatively. This is one reason why TG Pro has the fan control feature.

Orange - The fan speed is between 75-89% of the maximum. This is also usually ok if it's for a short time when the Mac is working hard, except if it's always in this range or red.

Red - The fan speed is between 90-100% of the maximum. This means the fan is pretty much maxed out. Again, this is ok if the Mac is working hard, except if it's continuously running red.

If a fan is always running red, even under a light load, it's possible that the fan is defective or it's clogged with dust.

To check for a defective fan, see the Check for defective hardware section.

For cleaning a fan, using compressed air around the air vents can help to clear out any dust and debris. If you're really adventurous, open up the Mac and use the compressed air inside to give it a really thorough cleaning. For information, search on Google for "cleaning inside Mac" or see an example under the "Get Rid of Dust" section of this Macworld article.

Check for defective hardware

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Again, going back to the main window, we'll be looking at the Diagnostics area, as indicated by #1.

There are three parts to this:

Last Shutdown: - This indicates if the last time the Mac was shutdown was normal, abnormal or forced. Some examples of a forced shutdown would be if the battery died or the Mac overheated to the point of turning off. This this case it is "Normal" since the user used the "Shutdown..." option from the Apple menu.

Fans: - This shows if any of the fans are labeled "bad" by the hardware. There is a special sensor that TG Pro checks to see if any of the fans are potentially defective. If one or more of them are, the name of them will be shown as indicated by #2. In this case, the "Right Side" was reported to be defective.

#3 - If there is a defective fan, a help button will be visible that when pressed will display a helpful popover with information about what to do. It means TG Pro has detected that one or more fans could be defective in some way. A fan labelled as defective might be working properly now although it's possible it might be about to fail.

This can be from a variety of reasons, the most common are:

A) Is that it's clogged with dust. To clean a fan, spray the exhaust grill with compressed air and then gently vacuum the dust that gets expelled.
B) It's a one off event and restarting the Mac may set the diagnostics back to normal.
C) The system has detected that the fan speed is abnormally going up and down.

Temperature Sensors: - If any of the temperature sensors are labeled "bad" by the hardware, they will be shown here. Just like for the fans, TG Pro checks a special sensor for this information.

Battery Health: - This shows the condition of the battery (if the Mac has one), any errors that have been reported along with the charge cycle count as indicated by #4. The condition will be one of the following:

Good - A well-performing power source.
Fair - A functional power source with limited capacity.
Poor - A power source that's not capable of providing power.

If the condition is Fair or Poor, there will usually some error messages provided by the system shown in brackets.

The charge cycle count is the number of times the battery has been discharged and charged. For example, if it shows 10, then the battery has been discharged by some amount and recharged (by plugging the Mac in to a power outlet). Most Mac laptops have batteries that are designed to handle up to 1000 charge cycles without any issues.

Using fan control to cool down the Mac

One of the best features of TG Pro is the full fan control. It's a special weapon against hot Macs and fans that have gone crazy.

Using the fan control is a great way to quickly cool down a hot Mac. For example, it's possible that even when the CPU temperatures are 95°C (203°F), the fans might be running at less than half speed. Increasing fan speeds to 75%, the CPU temperatures can drop to 65°C (149°F). That's a -30°C (54°F) change! Keeping the temperatures down and especially the CPU cool will help to prolong the life of your Mac.

There are three modes for fan control: System, Manual and Auto Boost.

To switch between these modes, open the main window, or click the status menu. You will see control like these:

from the Main Window

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from the Status Menu

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Choosing this fan control mode will revert all control back to the system. This means that TG Pro will no longer control the fan speeds in any way.



This fan control mode allows fine and immediate control over the fan speed. It is used to increase fan speeds to help cool down the components inside your Mac.

When adjusting the fan speeds, TG Pro will not allow them to go below what the system requires as a safeguard. With manual control, it is also possible to adjust each fan individually.

It's worth noting that is also possible to lower them by explicitly turning on a special preference, although this is a more advanced topic and there are risks involved which is why this is off by default.

Here's how to use manual control from the main window or the status menu:

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#1 - Turn on manual mode by choosing the "Manual" button from the three choices.

#2 - If there are multiple fans, there will be a button to link the speeds together as you change them. If the button is toggled, they will be linked, if it is un-toggled they will not be linked and will need to be adjusted separately.

#3 - Drag the knob in the slider towards the right to increase the fan speed and to the left to decrease it. Note that by default TG Pro will never allow the fans to go below what the Mac OS X system sets the minimum to be. This is a safe guard to prevent unintentional heating up of the hardware.
It's also worth noting that in these screenshots, the "NVIDIA GeForce GT 650M" is showing "N/A" for its temperature because it's turned off and the active graphics card is the "Intel HD Graphics 4000". This happened because on this model of MacBook Pro, it has two graphics cards which the system can switch between depending on which one is needed (power vs. performance).

Auto Boost

Having manual fan control is great although what's even better is having the ability to create rules for when and how the fan speed increases should occur. That's where the fan Auto Boost feature comes in.

Auto Boost uses rules to decide what speed the fans should be run at. When a rule becomes true (for example: Run the right fan at 75% when the highest CPU temperature is higher than 65°C), it will boost the fans to the set speed. You can have just a single rule, or create multiple ones to have "steps" for increasing the fan speed. We'll take a look at some examples for both types later on.

If multiple rules are true, Auto Boost will pick the one with the highest fan speed.

Let's start by looking at the Preferences (either from the application menu, or the menu bar icon) and choose the Fan tab. It will look like this:
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#1 - Start by choosing the type of power source the rules will apply to. On Macs that have an internal battery (MacBooks, MacBook Pros, MacBook Airs) you can choose between "Power Adapter" and "Battery". This allows the flexibility of having different sets of rules whether the Mac is plugged in or running on battery power.

#2 - Adjust the Auto Boost gradual time to what you prefer. This is the time is takes to switch between rules. So for example if it's set at 5 seconds, then there will be a 5 second smooth transition between rules. The longer the delay the longer it takes the fans to change speed. This feature was added to prevent the fans from quickly ramping up, down, up, down and so on.

#3 - Turn this option on to have TG Pro set the fan control mode back to System while the Mac is sleeping and return it back to the user set mode when it wakes up.

#4 - This can be safely ignored for now since we won't be overriding the system fan control.

Everything is setup, so let's make some rules!

Using a single rule

To create a rule, click on the plus button as indicated by #1 in the screenshot below. This will add a new rule.

Once there are rules in place, they can be easily copied between the power sources by clicking the "Copy all to Battery" or "Copy all to Power Adapter" as shown by #2.

Here's an example of a new rule and the configurations that can be adjusted:
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#3 - Which fan will this rule apply to. On Macs where only one fan exists, there will only be one option like in this case, it's "Right Side". If there were multiple fans, an added option would be "All Fans".

- What percent of the maximum RPM should the fan go to when this rule happens? 0% would be the minimum RPM, 100% would be the maximum, and 50% would be right in the middle. For example, if the minimum is 2000RPM and the maximum is 6100RPM, setting it to 20% will raise the fan speed to 2820RPM.

#5- Where the rule gets the temperature to compare. There are four built-in types, and then a list of all the temperature sensors:
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Any Sensor- The temperature threshold will apply to any sensor. For example, if the rule has the "is above" temperature defined at 50°C and any of the sensors goes above this, the rule will be triggered.

- The rule will always apply (unless another rule that is triggered has a higher fan speed).

Average CPU
- The average temperature of all the CPU sensors.

Highest CPU - The highest temperature of all the CPU sensors. This can be very useful since it's usually the CPUs that get quite hot. This way if any of the them goes over the threshold, the rule will be triggered.

Then there all the temperature sensors to choose from. Choosing one of these (for example, "Platform Controller Hub Die") will cause the rule to only compare against that temperature.
#6 - The temperature threshold that would cause the rule to be triggered. For example, if the rule was for "Any Sensor" and the temperature was set at 90°C, then whenever any sensor goes above 90°C the rule would be triggered and the specified fan speed would be increased to the desired level.

#7 - To remove a rule, simply click the X button.

Using multiple rules

The real power is being able to use multiple rules to have "steps" for the fan speed as the temperatures increase, or adjusting individual fan speeds as needed.

Let's look at an example where the fan speeds will be always be boosted by at least 20%, then incremented each time the hottest CPU temperature goes up by 5°C (9°F):
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In this example, there are five rules, with the first one ensuring that the fan is always running at at least 20% of the maximum. For example, if the minimum is 2000RPM and the maximum is 6100RPM, setting it to 20% will always raise the fan speed to at least 2820RPM.

There other four are all similar in that they move the fan speed up by 20% each time the temperature of the highest CPU sensor increases by 5°C (9°F). This allows the fans to ramp up in steps depending on the CPU temperatures.

If the highest CPU temperature starts to go down, the rules will turn off an needed. For example, if the highest CPU temperature gets to 83°C (181°F) then the rule that boosts the fan to 100% will trigger. Then as the hardware cools down, if the highest temperature drops say to 72°C (162°F) then the rule that will be triggered is the one that boosts the fan to 60%.

With this type of setup, the Mac will stay quite a bit cooler than it would compared to running in System fan control mode.

Changes for 2018 & 2019 Mac Models

Apple changed the way the SMC is implemented in the 2018 and 2019 Mac models, which includes the MacBook Pros, Mac Mini and iMac Pro models. Instead of using the way it's been since 2007 with a separate chip, it is now integrated into the iBridge (T2 chip) module. The result of this, is the existing methods TG Pro uses for fan control didn't work. We did extensive R&D to determine how to control the fans for these models along with the safest way to do it. We discovered is that is it possible to change the fan speeds although this completely overrides the system where it is not able to increase or decrease them.

After going through a few different ideas on how to safely implement fan control for these models, we came up with a solution that we believe is the best one for now. This involved making a few changes to the way the fan control works for these models to ensure that they can't be accidentally set low.

The following sections detail the changes: Max, Auto Max and Override System.

All other features, such as logging, temperature sensors, fan information, notifications, etc are all the same as with previous models.


Note: This mode is only available for 2018 & 2019 Mac models (which have the T2 chip)
To avoid a situation where a user sets the fan speed to a low rpm, forgets about it and the system is not able to increase it, we've changed Manual into Max mode. When switching to this mode, TG Pro will automatically boost all fan speeds to their maximums to provide a quick way to help cool down the Mac. This should be especially helpful for users who have the Core i9 2018 MacBook Pro which can heat up very quickly.

To override this and use Manual mode instead, see here.
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Auto Max

Note: This mode is only available for 2018 & 2019 Mac models (which have the T2 chip)
This is the same as the Auto Boost fan control mode, except each rule is set to 100% of the max fan speed. The reason for this is the same as for the Max fan control mode.

To override this and use Auto Boost mode instead, see here.
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Override System

Note: This mode is only available for 2018 & 2019 Mac models (which have the T2 chip)
We're skipping ahead a bit, although we wanted to put this here so it's all organized. This option is described in detail in Overriding system fan control and is used to completely override the system so only TG Pro can control the fan speeds. Only use this if you need to lower the fan speeds temporarily using Manual mode (ex: for audio recording) or to completely replace the fan control using Auto Boost mode.

Use Manual instead of Max

Enabling this mode will change the Max fan control mode to Manual and provide sliders to set the fan speed.

This feature will override the system fan control since that's the only way to control the fan speeds on these Mac models. So keep that in mind when adjusting the fan speed using the slider.
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Use Auto Boost instead of Auto Max

Enabling this mode will change the Auto Max fan control mode to Auto Boost and provide the option to set the fan speed for the rules.

This feature will override the system fan control since that's the only way to control the fan speeds on these Mac models. Because of this, there must be enough rules setup to properly increase the speeds as needed. See Completely override system with custom fan control section for details on how to setup the proper rules.
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Overriding system fan control

One of the newer features of TG Pro is the ability to completely override the system control of a particular fan. This is an advanced feature and should only be used if you know that you need it - otherwise, please leave it off.

Once this is turned on, TG Pro has complete control over the fans and the system will no longer be able to raise or lower them. This will occur once the fan mode is switched to either Manual or Auto Boost and a fan speed is set. The danger in this is that the hardware can potentially overheat if the fan speeds are set too low and the Mac starts to get hot.

The system will not automatically increase the fans when the Mac heats up. Use at your own risk.

The most common use case for wanting to turn this feature on is to lower a fan that is always running at full speed, which can occur when replacing the HD in certain iMac models. To read how to use this feature to fix the full speed fan, click here.
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To turn this feature on, open the Preferences and choose the Fan tab. At the bottom, there is a checkbox for each fan. This allows the ability to override the control for one particular fan and leave the rest to be managed by the system. Once it is enabled, there will be a symbol in both the main window and status icon to show it's active.

Main window

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Status icon

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Fix iMac fan noise after HD replacement

If you've replaced your iMac's hard drive and you notice that one of the fans is always running at full speed and it's really loud? If so, you're probably going to like TG Pro. It has the ability to tame the fan and adjust it based on the temperature of the drive or of other sensors.

When the drive is replaced, it's very common to hear that a temperature sensor or cable was broken or unseated. When this happens, the system gets no response from the sensor responsible for the HD temperature and therefore decides to full the fan at full speed. This can be very annoying (and loud).

To trick to fixing this is to use TG Pro to override the system control for the HDD fan, and have it set the speed. Depending on if the replacement drive is an SSD (Solid State Drive) or a traditional HDD, the settings will be different.

To setup it up, start by opening the Preferences and choosing the Fan tab. Make sure the "Disable fan control when Mac is sleeping" checkbox is unchecked, as shown in #1 below. This will ensure that the HD fan speed will continue to be lowered in sleep mode.
Note that no matter which type of drive is used as the replacement, the iMac fan will still be labelled "HDD".
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Next, add the following Auto Boost rules, depending on which type the new drive is:

Using a SSD

SSDs run a lot cooler than traditional drives since they have no moving parts. Because of this, it's usually safe to set the HDD fan to a value close to the minimum and just leave it there.

Remember to check the "Override System Control" for the "HDD fan" so TG Pro can lower the speed.
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Using a HDD

HDDs can heat up the more they are used since they have a platter that spins inside. So it's necessary to add a few Auto Boost rules to ramp up the fan speeds as the drive heats up. First though, the option to enable the checking of drive temperatures must be enabled.
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To enable the checking of drive temperatures, open the Preferences and choose the Temperature tab. Then make sure the checkbox in 1# is checked.
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Then add the Auto Boost rules from the two screenshots above. There should be ten rules - each one increasing the fan speed by 10% for every 1°C in temperature change. If you're using fahrenheit, increment by 2°F in each rule.

Now, make sure the Auto Boost mode is enabled and your iMac will now be a lot quieter!

Completely override system with custom fan control

In some cases, it may be desirable to completely override the system fan control and use a custom algorithm. This is possible using TG Pro by combining the power of Auto Boost rules with the override system feature.

Please keep in mind doing this will completely replace the system fan control when the fan mode is set to Auto Boost. The system will not be able to increase or decrease the fan speeds which can cause the Mac to overheat if the fan speeds are set too low.

While this can be a very powerful feature, use at your own risk.

To set this up, first enable the override system feature for all the fans. Depending on which Mac model you have, it will look like this:

For 2018 and 2019 Mac models (which have the T2 chip)

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For all other Mac models

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Now that TG Pro is completely overriding get system, Auto Boost rules must be added to increase the fan speeds as the temperatures increase. This is very similar to the Multiple Auto Boost Rules section with the exception that there must be rules to go from 0-100% of the maximum rpm (Note: 0% is the minimum rpm). Otherwise, the fans will never be able to increase to their maximum rpms, which is needed when the temperatures are hot.

Here's an example set of rules:

• Fan speeds will always be at least 10%
• Fan speeds will be 25% if any sensor is above 40C
• Fan speeds will be 50% if any sensor is above 50C
• Fan speeds will be 75% if any sensor is above 60C
• Fan speeds will be 100% if any sensor is above 70C

The rules can also be different depending on if the Mac is running on the battery or is plugged into a power supply (read more about this here).
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To enable this, change the fan control mode to Auto Boost and TG Pro will adjust the fan speeds exactly to how they are set according to the Auto Boost rules for the current power source!

Saving information to a log file

Sometimes you might want to have all the temperature, fan speed and diagnostic information saved to a log file that you can view later.

TG Pro saves the log file in the CSV (Comma Separated Values) format. It's a standard way of storing data so it can easily be imported into an app like Numbers or Excel.

Each time the app checks the temperatures and fan speeds, it writes a new row into the CSV log file.

To setup logging, open the Preferences and choose the "Log" tab.
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#1 - To enable logging, check the "Enable Log" checkbox.
#2 - Choose the location where the log file will be stored. The default is ~/Documents/TG Pro Log.csv which can be kept if you'd like.
#3 - Choose which information will be stored in the log file. Use the option for ISO 8601 dates to have the log file names in the format YYYY-MM-DD.
#4 - Choose when the log file is created. The options are:

Never - This will continuously append to the log file which over time can get large.

On app startup - The log file will be erased and start over each time TG Pro is opened.

Every day - Each day at midnight, the log file will be erased and start over.
Note: Alerts may be shown in the log file if any of the temperatures exceed the threshold set in the Notifications tab of the app preferences. For example, if the app is setup to show a notification if any temperature goes above 100C, any temperature that is above this and output in a log file will have ALERT: prepended to it.
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Get notifications when it's too hot

TG Pro has the ability to display a local notification or send an email when temperatures are above a set threshold, as well as some other triggers.

Notification Center

The first and more common type of notifications are local ones that go through the Notification Center on OS X 10.8 (Mountain Lion) and up, and through Growl on OS X 10.7 (Lion).

Let's take a look at them:
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#1 - There are two options here:

Notification Center - Check this checkbox to turn on local notifications that will appear in the Notification Center (macOS 10.8+) or through Growl on older systems running macOS 10.8 (Lion).

Email - This is described in Email Notifications

#2 - To get notifications when the temperature is over a set threshold, check the "Temperature is above limit" checkbox.

Then move the sliders to a temperature you'd like to get notifications for. Now what to set these to is a bit of a personal preference of how hot is "too hot". Some decent values to start at would be:

Any Sensor - If any sensor goes above 100C (208F), you probably want to know about it since the fans might need to be turned up (see Increasing fan speeds to cool the Mac down) or a component might be overheating (like the power supply, GPU, etc).

Highest CPU - If the highest CPU temperature goes above 103C (212F), again it's probably worth while to know about for the same reasons as above. On most Mac models, the thermal limit of the CPU is 105C (221F) so if it gets to 104C, the CPU may be throttled (slowed down) in order to cool it down. Boosting the fan speeds in this case may prevent the throttling.

#3 - Some extra options for showing notifications when the fan Auto Boost feature turns on/off and if the last shutdown code was not normal (see Finding defective hardware for more info on this).


The second type of notifications are sent through email and are really handy for remote servers where you want to know if they are overheating before any damage or data loss occurs.

Setting it up is very similar to the Notification Center ones above with the exception of turning on the "Email" checkbox and filling in the email account info.

Note that the emails sent do not require an email account setup on the Mac through Mail or any other mail client.

Email notifications contain the following info:
  • Type (temperature, fan auto boost on/off or shutdown)
  • Mac model
  • Hostname
  • OS X version
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#4 - Check the "Email" checkbox to turn on email notifications.

#5 - Start by filling in the "User Name" text field with the email address that will be used to send the notifications. Once you move to filling in the password field, TG Pro is smart enough to try and pre-populate the rest for you. Using an email from a common domain (Gmail, Yahoo, iCloud, etc) will automatically fill in "Outgoing Mail Server", "SMTP Port" and "SMTP Encryption Type".

#6 - Once all the email fields are filled in, add the address of who will receive the email notifications, then click the "Send Test Email" button. This will ensure that when there is a real notification that the email can be sent properly. Check the mailbox for the receiver address to verify that the test email was received.

In the screenshot above, the email notifications will come from "kingbob@minions.com" and the test email will be delivered to "stuart@minions.com".

Here are some examples of what the email notifications look like:
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Reset to factory defaults

One of the great features of TG Pro is that there's so many options and things to try out. Sometimes though, it makes sense to be able to reset everything back to the way it originally came when it was first downloaded. This is why we added this feature, starting in v2.27.

To reset all settings, which will also remove any Auto Boost rules created, open the preferences, choose the Applications tab and click the button labelled "Reset app to defaults...". Once that's been clicked, there will be a confirmation dialog and if Yes is chosen, the app will reset itself and relaunch.

Note: This will not remove the license, so it won't have to be re-entered.
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If you still have some questions, please check out the FAQ for TG Pro and if the answer isn't there, please feel free to email us anytime at support@tunabelly.com
who we are
Tunabelly Software is a Canadian software development company.
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what we do
Specialize in making amazing macOS, tvOS and iOS apps.