My overheated MacBook 2016 is all right

Notebook & PC

Midsummer is finally here and may last for a while - short breaks to cool off people, animals and machines cannot be ruled out. What some people like because they populate beaches and beer gardens will be rather uncomfortable for others, for example older people or residents of attic apartments.

It's not just people who complain about the heat in summer, machines also groan under the increased temperatures: Processors, graphics chips, SSDs and hard drives in a Mac all consume energy and have to release it back into the environment in the form of heat. The higher the temperatures there, the more difficult it is to cool. The same applies to the iPad and iPhone. Apple has designed all of its devices for operation at ambient temperatures of up to 35 degrees - above this it can become critical. The use of energy-saving components and sophisticated cooling means that overheating problems have become rare. One or the other model does not cope with the heat as well as other devices and switches off as a precaution. It becomes particularly critical with the fanless Macbook 12 inch. This automatically reduces the power consumption of the processor if it gets too cold inside, but it can reach its limits faster in summer than models with a fan. But panic is not appropriate, we put the 2015 Macbook under full load on the hottest summer day and only had problems with operation in the closed car.

Without fan

The Macbook 12 inch Retina does not need a fan and has to rely on the passive cooling of the case. If the processor gets too hot, it reduces its clock rate. This video shows how water cooling prevents the heat collapse and how the CPU works longer at a higher clock rate. Although the solution is not practical, it shows how important thermal contact to a cold reservoir is for heat dissipation. Maybe someone will find a solution with a cooling sleeve?

Why a Mac gets too hot: A lot of power, a lot of heat

An indication of the thermal sensitivity of the various Macs is the tests we run under full load. The 15-inch Macbook Pro with Retina display and separate Nvidia graphics processor lets its fans work at high speed under load in order to get the heat out of the device. The current base model, which is satisfied with the integrated graphics core from Intel and also clocks lower, has to dissipate less load under heat than the 13-inch version of the Retina Macbook, which is why the fan speed only increases a little. With the Macbook Air, it is not particularly high-performance components that are the cause of rapidly rotating fans, but the limited space for cooling and fans. You can therefore work up a sweat under load and high outside temperatures and you have to audibly activate the fan.

Switch graphics processor

To see whether the separate graphics processor is activated, start the Activity Monitor application (Programs / Utilities) and switch to the “Energy” section. In the “Requires high-performance GPU” column, the applications that use the separate graphics processor are then marked with “Yes”. This includes, for example, iPhoto, iMovie and Aperture. If no application is listed with "Yes" in the column, the Macbook is working with the integrated graphics processor. However, OS X does not offer the possibility of permanently switching to the integrated graphics processor. If you switch off the option “Automatic change of graphics modes” in the system setting “Save energy”, the Macbook always uses the separate graphics processor.

It looks more relaxed on the desktop computers. With one exception, the fans of the iMacs we tested did not go too high even under load. Only the top model with the most powerful graphics chip Nvidia Gforce GTX 780M and the quad-core processor clocked at 3.5 GHz has to counter the given performance with clearly audible cooling under load. With the Mac Mini, only the fan of the version upgraded with a Fusion Drive and the 2.6 GHz quad-core processor is audible under load; the simpler models let their fan continue to work at a low speed. This also applies to the base model of the Mac Pro with four processor cores, while the big brother with eight cores has to dissipate a little more heat, but still with moderate fan speeds. iPad and iPhone have no fans and can therefore only switch off or switch off certain processes if there is a risk of overheating. If the device gets too hot, it can, among other things, darken or switch off the display, stop charging and switch the cellular phone chip to power-saving mode. If this does not help, a message appears stating that the device must first cool down before it can be used again. You then turn it off and wait for it to recover.

Monitoring tools

If you want to display the fan speed as well as the temperature of the processor and other system components on a Mac, there are a number of utilities for this purpose. The most comprehensive information is available with Bjango's iStat Menus app. The program, which costs around twelve euros, not only shows the temperatures of the individual system components and the fan speed via the menu bar, but also the utilization of the memory and processor and the state of charge of the battery. The System Monitor app from Marcel Bresink, which is available from the Mac App Store, is cheaper at EUR 4.50, but it provides less information, especially with regard to the temperature of the system components. The Hardware Monitor and Temperature Monitor programs from the same developer are no longer compatible with Macs released after 2012. There are also free programs for monitoring the fans and the temperature such as Smc Fancontrol and Macs Fan Control. These programs can also be used to control the fan speed, which is normally regulated automatically by the system. However, if the speed is set too low here, overheating can occur, which is why it is usually better to keep your fingers off that and limit yourself to displaying the values.

Tips for cooling

Switch off location in the sun

You should not leave your iPad, iPhone or Macbook in a vehicle parked in the sun or expose it to direct sunlight for a long time. In addition, some processes place a particularly heavy load on the device because they are very computationally intensive, and they also heat up the device. With the iPhone and iPad, this includes GPS tracking and navigation as well as games with complex graphics. It is therefore advisable to temporarily forego these functions when it is very hot.

No game sessions in the heat

Macbook owners should also not use graphics-intensive games for a long time in high ambient temperatures, which is especially true for the Macbook with a separate graphics processor, as this is particularly game-compatible and powerful, but also produces more heat than the integrated graphics processor. Intel chip in the other Macbooks. Programs for editing videos and music such as Final Cut Pro and Logic Pro are particularly computationally intensive. It is therefore better to postpone long-term calculations to times or places in or where it is cooler.

Do not cover the ventilation slots

All current Macbooks have a metal housing that, in addition to the fans, ensures that heat is removed. It is therefore counterproductive to place the devices on soft surfaces such as pillows and blankets when you make yourself comfortable on the sofa, as these cannot transmit the heat and you also run the risk of accidentally covering the ventilation slots. Some suppliers have documents for operating the sofa, such as the Belkin Cushdeck, or you can use a normal tray.

Use the Macbook stand

If you operate the Macbook on the desk, a notebook stand can provide better ventilation and a more ergonomic screen height. Desktop Macs are less affected by high ambient temperatures, as rooms rarely get so hot that cooling problems arise, and the computers are usually set up in such a way that they can freely dissipate the waste heat into the environment. Macs that run under full load for several hours, such as rendering, should be set up in a cool room.