VRAM in Xfire question?

Altecice · September 15, 2014

Hey guys I need a quick question answered.

I was messing around with my two 290x's with GPU-Z, if you didnt know they have 4GB of VRAM each. Now i know that (or i think i know) that when you crossfire/SLI you don't get double VRAM as it mirrors. But i got confused once a read GPU-Z and my cards.I noticed that my "Memory Usage (Dynamic)" was hitting 7096mb. How is this possible? when they only have 4096 and if it mirrored there would be no more.

Does GPU-Z count the VRAM usage as 4096+4096 = max VRAM. So for instance if card 1 was using 2gb and card two was using 3gb of VRAM GPU-Z would report it as 5GB?

Thats the only explanation I can think of that makes any sence to me.

PS- I was running Sniper Elite v3 @ 5760x1080p (ultra and x2 super sampling)

AlwaysFSX · September 15, 2014

But wouldn't both cards have the same usage since it's mirrored?

Altecice · September 15, 2014

But wouldn't both cards have the same usage since it's mirrored?

Yeah thats what I always thought. so it would only have 4096. Yet I was able to get a range of 3gb-7gb (depending on settings)... baffled me

AlwaysFSX · September 15, 2014

Yeah thats what I always thought. so it would only have 4096. Yet I was able to get a range of 3gb-7gb (depending on settings)... baffled me

Maybe each of them have 3.5G in the memory?

Altecice · September 15, 2014

Maybe each of them have 3.5G in the memory?

Yeah but I always assumed that in crossfire/SLI each card mirrors its RAM so if 1 card had 4096 two card would still only have 4096. so surely 4096 would be the maximum VRAM in XFire?

AlwaysFSX · September 15, 2014

Yeah but I always assumed that in crossfire/SLI each card mirrors its RAM so if 1 card had 4096 two card would still only have 4096. so surely 4096 would be the maximum VRAM in XFire?

Per card technically. I think it would be listed as 8192 though.