Asus X99 Deluxe PCIe slot 1 not detecting my GTX970 in SLI

[Frey]

The graphics card PCIe x16 slot 1 will not recognize a functioning X16 Nvidia GTX970 graphics card. I have been using 2 GTX970 in SLI in slot 1 and 4 since the build over a year now. Nothing was added to the computer or any change of hardware. It completed a Windows update, I came back from work and turned the computer back on and PCIe slot 1 was not recognizing my GTX 970, only the other card in slot 4 was recognized. Both cards work in the other PCIe slots at x8 and both cards work in my other computer. Neither of my 970's are even recognized as being plugged into the first slot in bios or in windows (fans and lights work on either 970 card though). I'm using the second card in slot 4 so I can get a display (all other PCIe slots are seem to be functioning at x8 and x4). This is the second time I've sent this board into ASUS for repair and all that was done the last two times was a re-flash of the bios which I had already done. I have a spare GTX 960 and a GTX 460 and only the 460 works in slot one, but neither of my gtx 970's or the 960 will work in slot one on this board. I'm running with a i7-5820K so my config is slot 1 and 4 on this board, and like I said I can have both GTX970 plugged in (like in SLI) but I have to plug into the card in slot 4 to get the monitor up and the other card (no matter which 970) will not be detected as plugged into slot 1. I can't figure it out and ASUS is not being very cooperative on giving me a replacement board as this is what I requested the last time I sent it in (to be repaired, yeah) I knew they would just ship it back without fix, and that's exactly what happened.

 

[helpstar]

Reset BIOS, clr CMOS while the cards are plugged. (without power from wall plug)

All switches in default position?

 

[Frey]

Reset BIOS, clr CMOS while the cards are plugged. (without power from wall plug)

All switches in default position?

I tried that before I sent the board in. I didn't take the battery out though. I think all the switches are in default, I didn't change them from factory. I also updated my post to change that the GTX960 I tried in slot 1 isn't detected either. The 460 I have is detected though so I know that slot is getting power, but it isn't seeing any of my newer graphics cards?

 

[helpstar]

check the cpu socket pins if some are bent

set with the 460 inside BIOS the PCIe lane (link speed) to gen2 and try the 960 again

 

[Frey]

check the cpu socket pins if some are bent

set with the 460 inside BIOS the PCIe lane (link speed) to gen2 and try the 960 again

I've sent the board in twice already and checked the pins both times and didn't see anything bent, I would assume they checked that out as well (probably not though). I think I've already tried setting it to gen2 in advanced settings but I'll check it again with the 460 installed in slot 1 and see.

 

[Frey]

Just a quick (and very late) update for anyone who may be experiencing the same issues where they lose the x16 PCIe lane on their X99 motherboard. After reading up more about it I decided that it might be an issue with the CPU (intel 5820k) since the PCIe lanes are controlled directly from the CPU. I was only 2 years into the 3 year warranty on the CPU so I contacted Intel and had them send me out a new CPU for a swap. Popped the new CPU in and boom! Graphics card running at X16 in PCIe slot 1 was finally detected again. Not sure what happened to the the CPU as I never really overclocked it anywhere near where it would cause damage and didn't ever leave it overclocked (I just didn't need the extra speed). After running off my second graphics card at x8 in slot 4 for over 6 months its nice to have both 970's running in SLI again.

 

[helpstar]

great it worked out for you. Eventually contacts on the faulty CPU were touched while installing.