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GTX670 Tri-SLI - bottleneck?

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I'm using EVGA Superclocked GTX670 Tri-Sli on an IvyBridge i7 3770K @ 4.7ghz. The Mobo is an Asrock Z68 Extreme 7 Gen 3.

GPU-Z is reporting the first card at x16/2.0, the second and third at x8/2.0

A few questions:

1. Is my CPU bottlenecking this? I think I could get 5.0ghz, but 4.7ghz was easy and I'm still on H100 cooling - don't want to go custom loop
2. Is my Mobo bottlenecking this? It advertized PCIE 3.0 but I think that's only for single GPU in the first slot with an Ivy Bridge chip. Or am I wrong?
3. Would RAM bottlneck this? I have 32gb RAM but they are standard 1600 chips - I'm not OCing it at all.

Thanks in advance.

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Whether or not your CPU is bottlenecking your 670's is up to your resolution. Given you did not mention one, that leads me to believe you have 1080p, as that is what most people have these days.

The short answer is "yes, most of the time".

The long answer is you have far too much GPU power for a single 60hz 1080p monitor and your CPU is plenty fast for the monitor, you just have wasted GPU power.

You should be getting 60 FPS in pretty much all games unless you push the AA to high and get vram issues. The CPU might be bottlenecking your FPS to something like 80 FPS... where your GPU might be able to push 100 FPS... But if you are on 60Hz monitors you only can display 60 FPS anyway so it doesn't matter. Turn on Adaptive Vsync and don't worry about your "bottlenecks" unless you are seeing fps sub 40.
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thepregnantgod said:
1. Is my CPU bottlenecking this? I think I could get 5.0ghz, but 4.7ghz was easy and I'm still on H100 cooling - don't want to go custom loop

A bottleneck wouldn't change the standard being used, just slow down the one in use.

Quote:
2. Is my Mobo bottlenecking this? It advertized PCIE 3.0 but I think that's only for single GPU in the first slot with an Ivy Bridge chip. Or am I wrong?

Right on all counts. You're using a Z68 board, which was before PCIe 3.0 became the standard. As a result, motherboards didn't really have the bandwidth for proper implementations. Your board is very likely PCIe 3.0 with single cards in the top slot only (and yes, you need an IVB chip to get PCIe 3.0 as well).

Quote:
3. Would RAM bottlneck this? I have 32gb RAM but they are standard 1600 chips - I'm not OCing it at all.

32GB is about six times more than you'll ever reasonably use, unless you're doing rendering or photo/video editing or using a RAM disk. It also won't impact which PCIe standard your board uses.

Cool.

So the PCIE 2.0 x16/x8/x8 doesn't really matter?

As for vRam all the cards have 4gb each.

Yes, my monitors are 60hz - so I know I'll be maxed at 60fps. I'm currently playing Skyrim at that resolution on Ultra settings - with only a few stutters - but I wanted to make sure from others who have more experience.

PCIE 2.0 x8 will only reduce your performance by maybe 2-3% - nothing to worry about. as for Vram the main issue is going to be the memory bandwidth not so much the amount - try setting your memory clock offset to something between +300-500 on each card if you can.

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Didn't toms do a review on ram recently? I thought it showed that 1600 ram vs 2133 had very little improvement and no improvement in most titles.. I'll see if i can find it. Oh and going from 2.0 x16 to 2.0x8 is only like 2-3% performance difference - not enough to really worry about.

Found the review.... It was using an AMD CPU... So no help really. Anyway I know ram speed is much less of an issue with intel builds. AMDs do see better performance with higher ram speeds while intels see much less - no point in really going above 1600 on intel system so you are fine.

icemunk said:
I would say your 1600 RAM would be a bottleneck

RAM speed has very little impact on performance. Going faster than DDR3-1600 does improve your framerates, but it's pretty small. I consider this to be a worthwhile investment, since it's typically a 0.5% - 1% increase in computer cost, for a 1%-3% performance gain. That's a win in my book.

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and also the 8x crossfire bus with triple SLI, the 670s are gonna definetely bottleneck.

Actually, not really. PCIe has so much more bandwidth than is necessary it's insane. Basically, the standard is 2 generations ahead of the cards, in terms of bandwidth. We're only just now getting cards that see major performance degradations on PCIe 1.1.
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