PCIE X16 vs X8

[jamie0226]

I heard that using SLI/CrossfireX will lose some score on benching because of PCIE x16 changed in to x8,

I want to know if two GPUs on one card(without GPUs been under clocked) is faster than two cards because of PCIE bandwidth ??

 

[yassarikhan786]

Dual gpu cards more often then not run at underclocked speeds. So e.g. a GTX 590 is essentially running two under clocked 580's, so two stock 580's will be faster then a single 590.

 

[KING_OF_SAND]

I heard that using SLI/CrossfireX will lose some score on benching because of PCIE x16 changed in to x8,

I want to know if two GPUs on one card(without GPUs been under clocked) is faster than two cards because of PCIE bandwidth ??

If you had a 590 clocked at 580 speeds and you had dual stock 580s both on x16 x16 lanes thus having the 590 being x8 x8 each chip, there will be no difference in performance.

 

[Pr3d4t0r]

it makes no difference whatsoever, even 4x has still lots of bandwidth left to push even something like quad 7970s, I suggest you check out Linus Tech Tips video benchmarking these lanes at x4, x8 and x16, theoretically, a single card at x16 compared to two, 50% equivalents of the single, will only impact the performance by maybe a frame or two, which in a real life scenario is nothing really

 

[| raVen |]

Yeah there is not too much a difference between 16x and 8x.