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Thermalright cpu heatsink has a convex base on it, problem?

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Jan 5, 2023
Q: What do I do with this convex Thermalright heatsink? I think I should lap it flat.

So I have this new Thermalright ACP90-x45 cpu cooler, but it has this imo freakish convex base on it.

The Ryzen cpu I have, sitting now in the socket on the mobo, this cpu heatspreader is entirely flat.

I don't like the prospect of having this convext heatsink press on the cpu, and I think I should lap the cpu cooler base.

The cpu has a 'monolithic' core I read and so the cpu chip is at the center of the whole cpu.


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That is pretty steep. Must be an old cooler, and by old, I mean really old. 10 years at least.

Anyways, look at the IHS on your AM4 CPU. Look at the edges. It is like a bowl.

I would try it.
I will take another look at my Ryzen 7 Pro 5750G cpu. It did look really flat the last time I checked.
Many CPU heat spreaders are concave, i.e. the edges are higher than the center. Therefore, the convex bottom plat of the heatsink should match the shape pretty well.
I've got a Cryorig R1 Ultimate from a few yrs back & its dead flat in the middle & towards both sides but very slightly raised in the middle (opposite way).