Question Help Please - Second GPU missing / SLI unavailable after Windows 10 1903 Update

[RacinJason73]

I recently experienced difficulties with Windows 10 automatically upgrading from build 1803 to 1903. After many attempts to correct the issue since 1803 is about to go obsolete, I ended up having to complete a fresh, clean installation of Windows 10 to get it to update to 1903.

In doing this to update to 1903, I have now uncovered a new problem. My computer will not recognize my second GPU which is linked to the first GPU via SLI cable. It only recognizes one of the two cards installed. I have swapped the cards around, so I'm certain both GPUs are still functional. However, since the computer doesn't recognize the second card, I can't enable and configure SLI through the NVidia Control Panel and I have noticed significant reduction in video performance in games. I know the GPUs are physically installed correctly, because they worked prior to the update.

This is an older gaming computer built by CyberPower. It started its life as a Windows 7 machine and was upgraded to Windows 10 during the free upgrade program. It was working fine on Windows 10 build 1803. I updated so to have a supported build version of Windows 10. I am looking for advice on how to correct this within build 1903.

Listed below is my hardware configuration.

Motherboard: ASUS P9X79 Pro
BIOS version: 4701
Processor: Don't remember, will update.
RAM: 4x4Gb, 4x8Gb
GPUs: (two) MSI GeForce GTX660Ti 2Gb
NVidia Driver: GeForce Game Ready Driver WHQL Version 436.48 and GeForce Experience

 

[Fix_that_Glitch]

Before you do all this Did you reinstall all the motherboard maker drivers after you reinstalled windows?)-----So remove one gpu, then go in to device manager and uninstall the remaining gpu thru device manager. Uninstall Nvidia drivers. Restart the computer, the computer will start in vga mode . (Hopefully IT WILL install a driver for the gpu in windows.) Then reinstall the Nvidia drivers. Turn off the computer and install the second gpu and sli bridge. Restart computer and see if it recognizes both of them now.

 

[RacinJason73]

@Fix_that_Glitch - THANKS for your input!

I actually hired out the Windows 10 reinstall with an IT professional (long story - insanely busy right now and was hoping to avoid all this extra "fix it" work). He did reinstall drivers, but am uncertain if he started with the motherboard maker drivers. I do know he installed the latest NVidia drivers after installing Windows 10. The BIOS is already the latest version.

In noticing the issue with the second GPU not being recognized after the reinstallation of Windows, I did try to remove the NVidia drivers through add/remove programs and then reinstall, hoping to trigger recognition. That didn't work.

I then tried swapping positions with the GPUs - no change.

I then removed one of the GPUs (the one in the initial, single GPU PCI-E location on the motherboard) - no change. I swapped GPUs (thinking I might be able to detect if one had gone bad) - no change.

When I then put a single GPU in the initial, single GPU PCI-E location, the computer beeped and would not boot - or at least I had a black screen so could not see if it was booting. Swapped GPUs - same result. So, I reverted to putting them both back in, but Windows still only recognizes the one.

In reading through several threads, I think I should try Display Drive Uninstall (DDU) in SAFE mode and reinstall drivers to see if that nudges Windows 10 to recognize the second GPU. If not, then I think I'll try DDU again, remove the second GPU, open in SAFE mode and try again. If that works, then reinstall my second GPU and see it Windows will recognize it. Does that sound like a reasonable process to fix the problem? I'm open to suggestions.

 

[RacinJason73]

Well. I tried Display Driver Uninstall (DDU) in SAFE mode and reinstalled drivers after reboot. Windows still doesn't recognize the 2nd GPU.

@Fix_that_Glitch
I tried your procedure by first removing one of the GPUs (left the one in PCIe 3.0 x16 slot 4 - more on that later). Rebooted, then entered SAFE mode, uninstalled video adapter device through device manager and ran DDU. Rebooted.

Thankfully, it recognized the single GPU and dropped in an earlier version of the NVidia driver. I then installed the latest NVidia drive - selected clean installation. Rebooted. All stable, so shut down.

Installed the 2nd GPU (into PCIe 3.0 x16 slot 1), SLI bridge and turned on the computer. Still doesn't recognize the 2nd GPU. Tried reinstalling the latest NVidia driver anyway. Rebooted. No change. Only recognizes the single GPU.

Concerning PCIe slots, in the motherboard manual, it recommends a single GPU be installed in slot 1 and a 2nd GPU be installed into slot 4. This is where they were prior to Windows 10 1903. I repeated the process mentioned, except this time first removing the GPU in slot 4, leaving only the GPU in slot 1 ... as recommended in the motherboard manual. Rebooted. Computer does not boot. Doesn't even make it to BIOS screen. Beeps and displays some codes on the LEDs., which I don't know what they mean, if anything.

This is starting to feel more like a hardware problem. Both cards work, because I've also swapped them individually and both work.

How can I check if the PCIe 3.0 x16 slot 1 is working?

 

[Fix_that_Glitch]

Ok so go in to bios and tell me what version is listed please. It will be on first page usually in upper left hand corner. It will sau motherboard type and bios version #xxxx.

 

[RacinJason73]

I'm not at the computer at the moment, but I think what you're asking for was included in original post.

Motherboard: ASUS P9X79 Pro
BIOS version: 4701

Does that help?

 

[Fix_that_Glitch]

ASUS P9X79 Pro

Sorry yes you did include bios in original post. I read so many they all start blending together, sorry. Ah so pcie slot 1 seems to be the culprit. Does the computer boot when either gpu is put in slot 4?

 

[RacinJason73]

Sorry yes you did include bios in original post. I read so many they all start blending together, sorry. Ah so pcie slot 1 seems to be the culprit. Does the computer boot when either gpu is put in slot 4?

No worries. Happy to provide the info. again. The computer does boot normally when either GPU is installed in PCIe slot 4. So, I think that rules out the GPU as the problem.

 

[RacinJason73]

Bump.

How can I check if the PCIe 3.0 x16 slot 1 is working? How can I tell if the BIOS or Windows 10 even recognizes PCIe 3.0 x16 slot 1 even exists anymore? Is there a disable/enable option in BIOS or Windows 10 that could have been changed inadvertently during the Windows 10 update to 1903?

 

[RacinJason73]

BUMP.

Both GPUs now being recognized in PCIe slot 2 and slot 4 and able to run in SLI mode. It will not recognize a GPU inserted into PCIe slot 1 - the motherboard's recommended slot. So, it's was not the Windows 10 1903 update that messed up my GPUs - just a coincidence.

Question 1: Is there a diagnostic tool which can confirm if slot 1 is "dead"?

Question 2: With GPUs in slot 2 and slot 4, the GPUs are stacked right on top of each other (no breathing room). Is that OK? My first concern is temperature.

Motherboard: ASUS P9X79 Pro
BIOS version: 4701
GPUs: (two) MSI GeForce GTX660Ti 2Gb
NVidia Driver: GeForce Game Ready Driver WHQL Version 440.97 and GeForce Experience

 

[paulcheah]

BUMP.

Both GPUs now being recognized in PCIe slot 2 and slot 4 and able to run in SLI mode. It will not recognize a GPU inserted into PCIe slot 1 - the motherboard's recommended slot. So, it's was not the Windows 10 1903 update that messed up my GPUs - just a coincidence.

Question 1: Is there a diagnostic tool which can confirm if slot 1 is "dead"?

Question 2: With GPUs in slot 2 and slot 4, the GPUs are stacked right on top of each other (no breathing room). Is that OK? My first concern is temperature.

Motherboard: ASUS P9X79 Pro
BIOS version: 4701
GPUs: (two) MSI GeForce GTX660Ti 2Gb
NVidia Driver: GeForce Game Ready Driver WHQL Version 440.97 and GeForce Experience

Hi, I have a somewhat similar problem as yours. Did you ever find a solution?