Core i5 750 makes SLI suffer?

[Stu8018]

I recently upgraded to a Core i5 750 with a Biostar board with P55. I was reading a review of the CPU and it stated that since it was minus a memory controller compared to the i7 (making it cheaper) that anything but a single video card would suffer reduced performance. I upgraded specifically to run SLI (a pair of 8800gts 640s until I can afford gtx480s) but if this is the case am I better off just getting one really powerful card? Is there a way to compensate for the memory controller issue in bios?

[Zero82z]

Either you read it wrong, or whoever wrote that review didn't know what they were talking about. That is nonsense. Memory performance should have absolutely no effect on SLI.

[Icarus]

I checked into this when I got my i5 750 and all I've read is that it makes very little difference going from 16x+8x to 8x+8x unless your using real high resolutions (2560x1600+) and even then it's game specific and not usually a big amount...

[Stu8018]

He implied 8x8 configuration in SLI would perform worse than a single card using all 16 lanes. Not sure why that would be the case. It was Steven Walton from Techspot. Might over my head but I don't understand why that would be the case.

[Zero82z]

He implied 8x8 configuration in SLI would perform worse than a single card using all 16 lanes. Not sure why that would be the case. It was Steven Walton from Techspot. Might over my head but I don't understand why that would be the case.
So you're talking about PCI-E lanes then, not memory channels. That isn't what you said in your first post. In any case, the difference between 8x/8x and 16x/16x is minimal if not nonexistent in most situations. The only time you will see a difference is with very high-end cards and at high resolutions. As far as an 8x/8x SLI or Crossfire setup performing worse than a single card running in a 16x slot, that is definitely not true.

[sdbardwick]

HardOCP compared 16/16, 8/8 (http://hardocp.com/article/2010/08/23/gtx_480_sli_pcie_bandwidth_perf_x16x16_vs_x8x8/) and 4/4 SLI (http://hardocp.com/article/2010/08/25/gtx_480_sli_pcie_bandwidth_perf_x16x16_vs_x4x4/) and 16/8 setups (http://hardocp.com/article/2010/08/16/sli_cfx_pcie_bandwidth_perf_x16x16_vs_x16x8/).

Summary: Not much difference.

[x.clay]

from everything that I have read there isn't much difference between 8x/8x lanes and 16x/16x lanes. I have a P55 board and I have used crossfire (4890s) and SLI (GTX 470s) and it works great.

[rafal_iB_PL]

I agree. The way i5 could make SLI suffer is

a)Tri SLI - not enough bandwidth THEN, unless you apply NF200
b)not enough raw CPU performance

a) is almost academic, b) is rarely seen - those who can afford such cards surely can afford stronger CPU.