Z97X UD5H M.2 PCIE add on card with SLI GTX 580?

[jdakacurt]

Hello,

I recently purchased a 960 EVO M.2 card and of course noticed 800MBps top speed in the M.2 slot    So I purchased a PCI-e x4 M.2 add on card to utilize the speed of the M.2 SSD and as a work around. Now, I install this add on card in my free PCI-e slot, Windows 10 boots up fast, speed is what it should be now, BUT my pair of GTX 580s in SLI is now non functioning via Nvidia Control Panel. Yes I know they are old, and I should upgrade them, but money is tight. Forcing the X4 CPU PCI-e is the only BIOS option I see related to SLI/GPUs, and it does not solve the issue. The moment I pop the M.2 SSD back into the M.2 slot on the motherboard, SLI becomes functional again. Tried different drivers, etc but no luck. Is this a issue coming down to free motherboard lanes? Or...?  Any help appreciated!

Z97X UD5H REV 1.2 F10 BIOS
WINDOWS 10 64BIT

[shadowsports]

Greetings,
Nice MB 

Sadly, Gigabyte Z87, Z97 boards do not support NVMe M.2 drives, only AHCI or PCIe M.2 drives are supported.   

Here's the problem.

1 x PCI Express x16 slot, running at x4 (PCIEX4)
* The PCIEX4 slot shares bandwidth with the PCIEX8 and PCIEX16 slots. When the
PCIEX4 slot is populated, the PCIEX16 slot will operate at up to x8 mode and the
PCIEX8 will operate at up to x4 mode.  So inserting the adapter card in the x4 slot forces the 2nd GPU to operate at x4...  but the software is expecting x8 for SLI.

That said...  Try changing BIOS > Peripherals > PCIE Slot Config (CPU) from auto to x4.  F10 to save and reboot.  Do I think this will help, probably not, but its certainly worth trying.  I fear however this is ultimately a resource issue you cannot overcome if you want to keep your SLI.

Cheers