2-way SLI on Maximus V Extreme - best slots 8x/8x or 8x/16x?

[feniks]

I am looking at ASUS MVE manual and it seems that for 2-way SLI ASUS proposes using Intel CPU native bandwidth for both cards (8x/8x natively) using slots PCIe3.0_1 (top first) and PCIe3.0_2B (third from top). I know that switches/bridges may cause some lag, so it makes sense *IF* each of cards doesn't exceed the PCIe3.0 8x bandwidth (I think 670 2GB cards don't but I am unsure of it).
Also this configuration allows for better air flow between cards which probably matters if one relies on air cooling ... I don't, both cards are water cooled.

however I see there is also another config possible which is based on 3-SLI configuration and for 2-SLI it would suggest using both top first and second slots, PCIe3.0_1 & PCIe3.0_2A respectively for x8/16x.

tomorrow I will be installing my second 670 2GB for 8x/8x config for now and I hope it works fine (no lag related to PLX chip switching).

does anybody have some benchmarks comparing same cards and CPU clock (and memory) running 2 cards in each of mentioned configurations?

Thanks!

[rog-classified]

cant do. 2 cars take 6 space . sound card can only mount in last slot. even i do so it not gonna work because 2b.

stackoverflow13 wrote:
Well from my setup I can only advise the following: I have 1 in the top slot & 1 in 2b (3rd slot) I then have an asus card in slot 5 (2nd from last). If I move my souncard to any other slot (bottom) it disables the 2nd vid card.

[stackoverflow13]

That's really paniful. Why not just buy a flexible long sli connector from amazon or somewhere? Wouldn't this solve your issue? You wouldn't be able to use your souncard though.

[rog-classified]

120 mm sli brig? i have a one. do you think pcie x16/x8- 1 slot and pcie x8 -4 slot can work without any issue ? pciex8-4 is not a native slot.

[stackoverflow13]

It might do. I sorry I can't answer definitivily.

[rog-classified]

waiting for asus to answer that.

[feniks]

rog-classified wrote:

i mean the solid sli brig have the connecters to connect to the vga card. because my vga card is(asus gtx 680 d2top) big and the second connecter slot of the solid sli brig touch vga cards upper part and cant connect to the card the.

oh, I missed that fact, sorry man! how about the long flexible bridge for 2-way SLI I suggested earlier?

stackoverflow13 wrote:
That's really paniful. Why not just buy a flexible long sli connector from amazon or somewhere? Wouldn't this solve your issue? You wouldn't be able to use your souncard though.

exactly 🙂

rog-classified wrote:
120 mm sli brig? i have a one. do you think pcie x16/x8- 1 slot and pcie x8 -4 slot can work without any issue ? pciex8-4 is not a native slot.

it could, because that's part of tri-SLI configuration, no? I am using slots 1 and 2A now (also 8x/16x) and works fine. as long as you don't use 2B, you should be fine.

stackoverflow13 wrote:
It might do. I sorry I can't answer definitivily.

yup, we can only guess and it's actually he who must test it ii real life. I'd call ASUS tech support and ask, but they might not have a definitive answer either, since use of such thick cards is not in the manual LOL.

rog-classified wrote:
waiting for asus to answer that.

call them up.

[vertigo86]

Hi guys

Ive few doubts about my rig. I've a MVE win 3770k oc at 4.6 ghz and 2 gtx 680 dcu2t in sli. Because they're 3-slot cards ive installed the first one in pci slot 1 and the second one in pci slot 3 and not in the 2b. This because i wanted more room between cards, but in this configuration the first card is native to cpu and the second one is multiplexed by plx chip. During few heavy games played always at 1440p(crysis 3, far cry3) i noticed some fps drops so my question is:

1) is my system bottlenecked by cpu or by the "mixed" sli configuration (lag brought by plx)?
2) there is something wrong with my configuration?

Thanks

[stackoverflow13]

Iv've the same games as you and and similar GPU setup. For Crysis 3 I saw about 90-100fps with everithing set to max with no frame drops. But my cpu is a 2600k @ 4.8. It's certanily not cpu. When you say frame drops, how many fps are you getting? do you see stuttering or tearing? I know my GPUs' were maxed constantly throughout the game, but didn't get any issues. There will be a very small drop in performamnce using the plx chip but shouldn't be too bad. circa 2-3%. Did you get the latest nvidia drivers released last week?

[vertigo86]

I have frame drops from 60 (because of the vsync) to 25-27 fps with crysis 3 all set to very high 1440p and aa set to fxaa. Today i tested the cpu and it cant be because during the game it never goes beyond 60% of usage. I think it could be the plx or th ssd+hdd smart response at this point. I also tested the gpus and during game aee always at 98 99 % (nvidia 314.07). I hope it could be the hard drive combination becase if it's the plx i have to go watercooled for gpus because they were too close each other

[stackoverflow13]

Blimey that's a hell of a drop. I play at the same res as you too, since it's not cpu & my crysis 3 install is on a standard HDD not on my ssd, that leaves the GPU's. To be honest I didn't think you could get it to even SLI in slot 1+3 I thought it had to be 1+2b. This sure is an expensive hobby we have.