Hello Community,

I have just built a new Rig:

i75820k
Gigabyte GA-X99p-SLI motherboard
4x4GB Corsair Vengeance LPX DDR4
Noctua 15s CPU Cooler
(my old GTX 770 for now) gigabyte card
500GB Samsung 850 Pro EVO SSD
1TB HDD
850W EVGA GQ+ PSU

I put everything together and it runs/works really very well.

I was just verifying all the specs using AIDA64/CPU-Z/GPU-Z, and this is where I found a very strange issue.

Basically, my GTX 770 is only running at PCI express x16 1.1 mode. I AM AWARE of the downclocking that happens when the card is not in use, however despite running FURMARK GPU stress and GPU-Z render, this stays at PCI express x16 1.1.

Now, there is a setting in the BIOS of my motherboard to force a gen 1/2/3 of pci express. When I force PCI express 3.0 and try to run any GPU load my system will crash. When i force Gen 2, this will make the GTX 770 run at Gen 2 PCI express until reboot. If I DO NOT reboot, it is stable and persists at PCI express 2.0 x16. Once I reboot, It will reset to PCI express 1.1 and stay that way despite the bios setting set on FORCE gen 2.

Things I have done. This card was in my old system, and was functioning at PCI express 2.0 (in a sandy bridge system). It has been stable for 2 years or more. I moved the card to the other slots, and the same thing occurs. Additionally, I have updated my GFX drivers to the newest from nvidia, and my MOBO has the latest firmware update.

Of note, I have my system overclocked, including Core/uncore/memory. This symptom persists despite resetting the board to factory defaults.

I guess Im trying to figure out if this is a motherboard/GFX incompatibility or if there is something wrong with one of the components (namely the mobo).

Any help would be much appreciated. Thanks a lot. (If i need to return parts to microcenter, I have a week or so)