I just got an RX 6600 from second hand market and wanted to test it just to be sure. There was a Furmark screenshot on the seller’s pictures which is tested on Windows.
However when I did the Furmark test’s Linux version, while it was mostly similar, my memory clock shown as 875 MHz. It was 1750 MHz on seller’s test. I don’t know technical part behind this but this is a x2 difference I noticed. Also it was 14 Gbps on Windows while mine was 3.5 Gbps, the difference is x4 here.
There is probably a measurement difference between Windows and Linux drivers here, but like I said I don’t know the technical details behind these tests.
So, is this the same / different measurement or should I be worried about this card?


Isn’t AMD’s proprietary drivers horrible on Linux too? Anyway, I can set the clocks to highest on LACT, but for some reason Furmark still shows 875 MHz (3.5 Gbps).
IIRC proprietary driver doesn’t contain kernel component, it runs using Linux’s standard amdgpu driver (and it’s the kernel driver that handles power management and stuff). And I don’t think it’s terrible, there is just not much point to it since Mesa is good enough (and Valve also promotes using Mesa).