Liquid Metal Thermal Pad on dGPU?

Hi there! I am looking at the F16 reviews, and I started wondering about how to further improve the RX 7700S temperatures. Given that the F16 uses a off-the-shelf Coollaboratory Liquid MetalPad, which you can already find available for purchase from Amazon and on the official Framework marketplace, would you be able to apply the MetalPad on the 7700S?
You would of course need to protect the exposed contacts near the GPU die, as you would with Conductonaut. Do you think it would improve the thermals/noise levels?

I can’t answer this as I don’t know much about liquid metal cooling, but maybe this video is useful to you:

Here, iFixit disassembles the graphics module and they give you a good look at the insides, including the interface between the chip and the heatsink, so maybe you would be able to see something interesting.

You could try PTM7950 pads instead of the LM initially. I’ve tested my current laptop between PTM and Thermal Grizzly LM, the difference was really negligable. Enough that I actually went with the PTM as the final mount because the LM actually transfers heat too efficiently, it ended up making the laptop chassis too hot to use as well.

With the PTM pad, I get most of the performance of the LM mount, but the transfer is just less efficient enough that the chassis temps are fine. You can pick them up on Amazon too. JustJosh noted his FM chassis and keyboard deck were too hot to comfortably use when under load, I wonder if that’s a similar problem since they already have LM on the CPU.

Could be worth experimenting with when production units are delivered to end users.

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Well, technically more heat transfer to the GPU heatsink would not affect the keyboard / palm area temperature, since they are separate cooling modules, right?

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More heat in a system would mean that heat would transfer downwards. Also, though they use different vapor chambers they output to the same fans near the top of the device which go down into the top of the keyboard. The DGPU almost certainly increases surface temps

It’s hard to say, since JustJosh isn’t clear what loads he’s running for his temperature measurements. From the layout of heatpipes and fans from teardown images however, you can see how Frameworks distributed heatsink design can cause higher keyboard and palm area heating, especially on CPU heavy load, compared to a traditional laptop.

The heatpipes for the GPU are where a normal laptop’s cooling system would be, while the CPU pipes travel across the bottom of the keyboard area, instead of along the top.

Thinking on it, switching the CPU LM for a PM pad and changing the GPU to LM might actually be a good call. I know most things I do won’t require full CPU power, so limiting the ryzen chip via ryzen controller to lock temp/power limits, while ensuring the GPU can run full tilt when needed may be a good way to control thermals/noise.
Another option might be to place a layer of reflective tape on the top plate along where the heatpipes run to reflect more heat back into the chassis, though you’re just shifting the problem around in that case, it’ll heat the bottom more.

FM was probably thinking of full CPU power for those that need it when they designed the CPU block and LM interface, but for a lot of people, that’s probably overkill. Combined with the GPU output, it may heat the entire keyboard a bit much for comfort.

As someone who tried both tpm and liquid metal, just go tpm, there is barely any performance difference and tpm is easier and a lot safer.

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