Category Archives: Teardowns

MateBook X Pro 2019 Changes: What’s Fixed and What’s Not

I will outline what Huawei has and has not fixed in the 2019 MateBook X Pro compared to the 2018 model. You can find the more obvious talking points on The Verge and other normie sites, but here are the small engineering changes that I noticed during my teardown and testing.

Cooling

Screenshot from my teardown https://www.youtube.com/watch?v=Sxf_bU6OZXE&t=11974s

  • Huawei has perforated the regions of the heatsink above the CPU VRM. Whereas 2018’s VRM would overheat and cause the laptop to abruptly shut down when the CPU is pushed to around 15W, 2019’s VRM can supply over 30W continuously just fine. The CPU starts thermal throttling way before the VRM has any problem keeping up. I did manage to find the VRM’s limit though: with a fan blowing at the laptop’s bottom, the VRM bumps into a hardware current limit when the CPU reaches about 48W. That’s the maximum power the VRM is designed for.

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Huawei Revises MateBook X Pro with Speaker Distortion Remedy

Previously, the Huawei MateBook X Pro’s speakers would produce distortion because they rattled against the laptop body. As shown in this unit purchased in November, Huawei has addressed this issue by putting small pieces of foam underneath the speakers. Is this because they saw my original post, where I both pointed out the issue and introduced this very solution? We may never know.

Here’s Why MateBook X Pro Charges Slowly

Forget CPU and GPU thermal throttling — charge rate throttling is now a thing.

Exposed charging circuit with shielding cover peeled off. Plugged in, CPU idle.

  • The charging circuit doesn’t have enough cooling and tends to overheat.
  • Since the charging circuit and the CPU use the same heatsink, the heatsink already warmed by the CPU does not have a low enough temperature to efficiently cool the charging circuit.
  • The charging rate is temperature-dependent, but the charging circuit doesn’t seem to have a temperature sensor, so Huawei probably went super conservative about protecting the charging circuit and modeled its temperature after the CPU temperature.

Therefore, even when the CPU is a little bit warm, the charging rate thermal-throttles.

I will discuss solutions to reduce this as part my throttling elimination project.

Also, the recent BIOS updates seem to have slightly improved the charge rate.

Matebook X Pro Teardown

The only heatsink in this laptop is this big metal plate. In most laptops, a fan or two blow directly through a stacked-fin heatsink in a process called forced convection cooling. In the X Pro, heat spreads across the metal plate with the heatpipes' help, warming up the air inside the laptop. The small fan exhausts all this hot air and brings in new cool air using negative air pressure. It also generates some, but not enough, airflow across the heatsink plate.

The miserably small fan can spin at nearly 9,000 RPM, but the bar under it (where a heatsink with fins would usually be) is just one of the WiFi antennas.

The fan is the model BAZA0504R5H made by Asia Vital Components and rated at 5V 0.5A. This means it could theoretically use 2.5W when spinning at max speed (which happens to be around 8800RPM).

Look at how thin the fan is!

The fan has a sealed bearing.

The fan motor is 3-phase with 6 poles.

The copper base plate for the CPU.

Behind the keyboard is a pyrolytic graphite sheet to spread heat more evenly across the keyboard area.

See the motherboard with the heatsink off. The Nvidia MX150 GPU gets a thermal pad as if it were an Intel iGPU.

The back of the motherboard is covered with a plastic insulator film.

This is the motherboard's back with the plastic film removed.

The Nvidia MX150 (1D12 10W version) and its VRAM.

The motherboard has good component density. It's also the thinnest I've seen. The coil whine is insane on my unit.

The pop-up webcam's bottom and the springs for reducing the display cable's slack.

The WiFi card (Intel AC-8275) is non-replaceable.

Although the SSD is awkwardly under the heatsink, it can be wiggled straight out. I bought my X Pro on Taobao.com in China and it came with with a Samsung PM981.

The speakers under the speaker grill are tiny tweeters.

The tweeters fire upward through the grill, and they have a thin fabric filter cover.

Most of the sound comes from the bottom-facing speakers instead, which have much larger enclosures.

There is a cavity on each side of the touchpad, underneath the battery. The speakers could have extended into it like in the late-2017 HP Spectre X360 13t. Poor use of space? A little bit.

The hinges uses a simple rivet.

The display ribbon cables are similar to those of post-2016 MateBook Pros.

Huawei reportedly probed Apple suppliers to learn their display cable design (the one involved in #flexgate). As far as I know, this is the first laptop outside of MacBooks that houses the display controller inside the main body instead of the display assembly.

Unlike the MateBook X, there are no screws under the rubber feet. Instead, there are many plastic tabs that hold the back plate firm.

The back cover has many foam pads that press against the internals.

  1. Unscrew the screws.
  2. Use a guitar pick or similar tool to feel, locate, and lift the tabs.
  3. Pull the hinge side of the back plate first.
  4. No need to be gentle with the middle tab—it's spring loaded.
  5. The tabs near the touchpad side like to be slid out.

If your touchpad is loose or rattles, read this.

If you want to get rid of throttling and unlock more performance, read this.