SLI issues after motherboard swap

KIS

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Mar 22, 2010
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After replacing Gigabyte Z170X Gaming 7 with Asus Maximus Hero VIII on Windows 10 64bit running two 980ti's my SLI performance has significantly dropped. In games where I had 90 FPS in SLI as opposed to 55 FPS in a single card setup (at 1440p) my current SLI performance is on par with a single card but with visible stutter that I haven't encountered before (it's not micro-stutter but like when the whole picture jerks forward every 2 seconds or so). I've tried reinstalling the NVIDIA driver, rolling it back, changing the PCI configuration in BIOS to gen 3 for both GPUs, repositioning the SLI bridge on alternative spots on the GPUs. Nothing seems to work.

My thoughts are either the MB or the SLI bridge that comes with it are somehow faulty. Playing in SLI on the Gigabyte MB with its SLI bridge never saw such issues and was as it should be (30 to 80 per cent gain in FPS in games). Now I'm getting zero to 10 per cent gain and the jerky stutter.

Anyone had similar issues after a motherboard swap/with Asus Hero VIII? Would appreciate your input. Thanks.

Update: I've noticed my second PCIe slot on the MB (x8) is actually running at x4 while the first slot (with the master GPU) at x8 (which is normal in SLI). I guess this must be the issue but I have no idea why since these PCIe slots are not shared with other slots. Must be a faulty MB?
 

KIS

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Mar 22, 2010
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How would that affect SLI? All hard drives, files and applications work fine after the swap. I have reinstalled the video drivers too. How reinstalling the Windows would help this?
 

TJ Hooker

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Not doing a clean install of Windows after a hardware change (particularly CPU/motherboard) can lead to non-specific issues and/or instability, it's never a bad idea.

Is it only SLI performance that's affected? You didn't mention if single card performance is still on par with what you were getting prior to upgrading.
 

KIS

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Mar 22, 2010
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Haven't noticed any other issues so far. Single card preformance is the same. Reinstalling Windows means reinstalling all other applications and games which I'd like to avoid as a "maybe" solution only.
 

KIS

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Mar 22, 2010
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I've done a clean re-installation of Windows 10. The problem remains...