Having trouble understanding memory clock for gpu

NiBy

Prominent
Apr 20, 2017
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i understand the part about what it makes us of i think. The part im not getting is that there are people who put like +500 or +600 on the memory clock.

when testing with heaven benchmark. I noticed that when ever i switch between +375 and +275 i seem to get slightly better fps with +275. So the higher i got. the less fps heaven was showing. I could get over 500 and not have any artefacts or anything that would crash. but i would have less fps. Why does this happen?