Home » Thermal design in the Apple MacBook Pro is a disaster?

Thermal design in the Apple MacBook Pro is a disaster?

This blog post describes my steps to make my old Apple MacBook Pro run cooler in a warm climate under constant processor load.

When my Macbook turns older. Its somehow starts to feel slower. It’s weird because its still the same computer I bought four years ago. With every OSX version that Apple releases it makes my computer feels faster and it makes it feel slower. I have to explain this. My computer feels faster after the release of METAL for handling the graphics parts. But its feels slower of all the new software features that are integrated into every new OSX release. I also have that gut feeling that Apple isn’t giving OSX any priority anymore. The big money is made with the IOS devices. Why spent a lot of resources on OSX? Most things that are now coming to OSX and the Apple computers are innovations that are first made for the IOS devices. IOS get the optimization and new features first, OSX gets it later.

My late 2013 MacBook Pro 13 inch has an Intel 2.4Ghz I5 mobile processor with a TDP of 28 watts. This means that the processor can produce up to 28 watts of heat energy. The i5-4258U processor is a combined CPU and a GPU in one packaging. So the CPU and the GPU share the same footprint and share the same heat pipe that transports the heat from the processor to the heatsink. The fan is blowing this thermal energy out of the enclosure.

The cooling system in my Macbook Pro retina
The cooling system in my Macbook Pro retina

The i5-4258U has the base frequency of 2.4 GHz. But can use the Intel® Turbo Boost Technology to push the frequency up to 2.9 GHz if there is enough cooling. Lately, I’m using the Macbook day and night for the encoding of videos. So the processor is pushed to the limit. Because its here around 30 degrees Celsius the Macbook could not reach the full 2.9 GHz. It was hopping between 2.4 GHz and 2.7 GHz.  There has to be a way to improve this.

Every day its around 30 degrees celcius
Every day its around 30 degrees celcius

I start to search for a solution. On blogs and on Youtube videos the advice was to replace the thermal paste between the processor and the heat pipe. Thermal paste is a sticky solution that helps to transfer the heat from the processor to the heat pipe.  Apple doesn’t make their own laptops. They hire a company in China to do that work. The problem is that this company is using a low-quality cool paste that’s too thick, has bad thermal performance and it will lose it thermal conductivity over time. It’s total garbage. The solution is to replace the thermal paste with a high-quality brand. I searched for what kind of high-quality thermal pasta is available in the city. For around ten dollars I bought a small tube of Arctic Silver 5.

Arctic silver 5 on a Macbook Pro retina
Arctic silver 5 on a Macbook Pro retina

I removed the heat pipe and with alcohol, I cleaned the old thermal paste off the processor. There was indeed too much crappy thermal paste. It was everywhere. After everything was cleaned I applied a small drop of Arctic Silver on the processor and put the heat pipe back. It was a disaster. The MacBook was running awful. I removed the heat pipe again and saw the problem. I did not apply enough Thermal Paste. There was a big part of the processor not covered. I applied some more of the Arctic Silver and put the heat pipe back.

Wow. That was is big different. The MacBook feels snappier. With the old thermal paste, the laptop had hiccups when it had to do heavy graphics. But now it’s fluent. Lets put the MacBook to the test. Let’s encode some videos. My video encoding software only uses the CPU for its task. The GPU is almost running idle. This little adjustment is a big success.

The Macbook Retina can now run continues at 2.9 Ghz
The Macbook Retina can now run continues at 2.9 Ghz

One of the advanced of having a unibody computer is that the whole enclosure is a heatsink. This is also a disadvantage. Sticky sweaty palms. The whole laptop was feeling like a small backing plate. Not comfortable.  So I was looking for a solution to make the complete Macbook feel cooler and more comfortable at the hands.  In the local hardware store, I bought for one dollar a 12CM fan and hooked it up on the most worthless power supply ever. Don’t understand me wrong. The laptop was running great with the new thermal paste. It could run at full power. But it wasn’t comfortable to put your palms on the Macbook. So the fan was keeping the enclosure cool.

But the bottom plate of the MacBook Pro was still running super hot. I want the airflow of the 12 cm fan also to flow under the laptop. So I started to put things under the Macbook: Little blocks of plastic, a Bluetooth speaker or a coffee cup. It didn’t work. I had a cool laptop. But every time I moved the laptop it fell off its temporary plateau. When I was typing the whole laptop was wobbling. Let’s search for what kind of solutions exist to lift the laptop higher, but that I’m still capable to use the laptop without an external keyboard.

I will spare you the time I spend in searching for a solution. I read blog posts. I watched the videos. All the collected information I processed for a week. After that, I made the decision to buy the Xuenair MacBook Stand. A massive block of aluminum with a hinge. I paid 20 dollars for it.

Xuenair Macbook Pro laptop stand
Xuenair Macbook Pro laptop stand

The hinge makes the stand portable. You can fold it flat and put the stand in your bag. You can also fold the hinge up and use it as an iPad stand. The hinge is moving stiff so you can adjust the angle.

Xuenair Macbook stand open
Xuenair Macbook stand open

Now there is enough space under the Macbook for a good airflow. The hole at the back of the Xuenair helps with the cable management.

Xuenair Macbook Pro stand with a Macbook Pro retina on top
Xuenair Macbook Pro stand with a Macbook Pro retina on top

The chin of the laptop is close to the table. So I can use the trackpad and the keyboard while my arms are resting at the table. Not only does the Macbook got a better airflow under the enclosure. But the screen is now higher. It’s much more comfortable to work for a long time. I can hold my neck in a more natural position.  The stand is rock solid. I can type for hours and the MacBook is not wobbling. I think the Xuenair is a great product. I don’t have yet any experience with traveling. The stand is around 400 grams. Did I ever tell you that working with the combination of a trackpad and a mouse at the same time is god-like?

Xuenair Macbook Pro stand - Laptop is rock solid stable. Screen is higher
Xuenair Macbook Pro stand – Laptop is rock solid stable. Screen is higher

In the history, the GPU was mostly used only for games, acceleration of video playback and doing the graphical user interface.  Nowadays the GPU also responsible for heavy calculations. Take a look at the video editing software Final Cut Pro. It’s using the GPU to do the rendering of the videos, the analysis of the stabilization and the encoding of the final video. The CPU and the GPU are both used to give you a better experience. More and more the GPU is responsible for heavy repeating calculation task. In the first years under OSX OpenCL was responsible for this. Last years Apple is shifting to Metal for this GPU supporting calculations. The arrival of a Machine Learning Module in Mojave OSX 12 will accelerate the use of the GPU in your computer. The GPU will help the Apple Photos application for recognizing faces and objects in your pictures.

Let do some quick tests. This is not a hardware website where reviewers are doing hours of testing. Those are my own quick tests. I’m doing this for fun.

The Macbook is doing

  1. Final cut pro 4K export. This is using the CPU and the GPU;
  2. Permute HEVC encoding. This program is only using the CPU. The story is that ffmpeg isn’t using the GPU because of the low video quality in HEVC;
  3. Quicktime screen recording. This program always pushes the GPU frequency up to the maximum 1.1Ghz.

You can see that the processor is using around 30 watts. The GPU is running at 1.1 GHz and the CPU is running around 2.7 Ghz. Still in Turbo boost mode. I still get more CPU processing power than I paid for. But I don’t get the full 2.9 GHz.

Macbook Pro 13 inch running Final cut pro export. Permute HEVC encoding and screenrecord
Macbook Pro 13 inch running Final cut pro export. Permute HEVC encoding and screenrecord

Furmark is known as the GPU killer. It pushes the limit of your GPU. If your GPU can run a long time at a high load and a high temperature. Then you can assume it’s a stable and good GPU. It will be not the first time that a GPU is killed by the Furmark. So be careful.

  1. Final cut pro 4K export. This is using the CPU and the GPU
  2. Permute HEVC CPU encoding.
  3. Furmark running at 1024×640

This is interesting to see. The CPU is running now at 2.1 GHz. That’s under the base clock speed of 2.4 GHz. The GPU is running at 0.95 GHz. Lower than the maximum speed of 1.1 GHz. Is the processor throttling?  And that is something I want to know. Why is the processor not running at full clock speed? The total power consumption of the processor is 26 watt. Lower than the previous test.

Is there another reason why the processor is running slower. Is Furmark using all the memory bandwidth and the processor forced to run slower to keep up with the memory requests? But nobody will run Furmark in real life. So this is not an honest test.

Macbook Pro 13 inch running Final cut pro export. Permute HEVC encoding and furmark
Macbook Pro 13 inch running Final cut pro export. Permute HEVC encoding and furmark

After four years I have to realize that my MacBook Pro is an old machine. Its a great machine for my daily life. But for hardcore calculations, I can feel the machine is sludgy. If I do one task at the time the machine can keep up with my needs. Most video encoding I’m doing when I’m at sleep or when I’m not behind the computer. It takes some time. But I will get there.

The small adjustments I did to let the machine runs cooler is helping. The machine feels snappier because I replaced the thermal paste. The machine feels cooler because of the fan and the stand. The stand also improved in handling the machine better.

Leave a Reply

Your email address will not be published. Required fields are marked *