[SOLVED] When GPU installed, PC will not power on

[chase.velez.music]

EVGA GTX 970
Gigabyte Z92X UD7 TH (BIOS v F6)
Photon 750W PSU
Intel i5
16GB RAM Coursair (8GB x2 in primary slots)
Oct. 2018 Windows 10 update
Booting from Samsung EVO SSD

I have 2 notable issues related to my graphics card happening and I cannot find a solution to either. I purchased a (barely) used GTX 970 from my friend. It requires a 6pin & 8pin PCIe power cable to be plugged into the PCIe connector on my 750W PSU. when it is plugged in the PC will not power on. The fans make maybe a half rotation and you can hear an electrical buzz (sounds bad but most likely fan motors). Does not make it to POST. The graphics card functions on other computers but not mine (the graphics card functions). On my computer the problem persists on every PCIe slot & every PCIe slot will run a 750ti (not a slot issue). I reset my BIOS by removing the battery, additionally I flashed it to the most updated version, and I have made sure the BIOS is displaying the correct PCIe slot (not a BIOS issue). The computer will run with no problems if either A; the PCIe power cables are unconnected or B; the graphics card is removed or replaced with my older 750ti, AND C; people have used the same graphics card with the same motherboard in other builds (not a motherboard/processor issue). Just for sh*ts and giggles I unplugged and replugged my RAM and PSU peripherals for the same results (not a memory or PSU issue). I have obviously made certain the the GPU is mounted correctly.

The second problem which seems like it could be related is that I cannot update my graphics drivers. When I am able to power on my computer because the GTX 970 is not plugged in I encounter this error. Geforce Experience cannot update to the latest driver (417.35) because the error appears that it is "not compatible with the current version of windows". If I use DDU and try to manually update the driver from Nvidia, it says the same error after it checks compatibility. If I use a third party "clean" version of 417.35 that removes some sound drivers and stuff related to televisions it also appears with the same error (all in all, it is likely somehow a compatibility issue with my OS, however, the first issue may not be related since it doesn't even get to POST. I'm starting to think this may be due to the fact the the GPU is not plugged into the PSU)

So basically I'm really confused since there are two outstanding issues that could or could not be related to eachother. Either way, my graphics card does not work in my build and I need to get it fixed since it definitely is supposed to. All hardware works when tested individually but not when configured together. All software has been updated except for the GPU driver due to the compatibility error with the update process. And finally, all common troubleshooting techniques have been tested for both these issues.

May be worth noting that if I leave my graphics card plugged into PCIe but not into the PSU, and the PC is on, the fans will attempt to rotate but fail. This repeats every 10 seconds or so. So obviously it is looking for the PSU power, yet again when actually plugged into the PSU the entire PC fails to power on. 750W is more than adequate power to supply the entire PC.

Thoughts?

 

[Obakasama]

Typically a driver won't install if the device isn't present in the system. You can't "pre-install" a driver. I don't think anything is suspicious there in the behaviour you're seeing.

Gut reaction is the PSU. If possible, install this PSU in the other computer and check if that boots. Then install this GTX 970 in and see if it boots.

Or at the very least, boot up your computer (without the graphics card) and use something like HWiNFO to have a look at the voltage rail readings. It's not the best method, but should at least pick up the largest discrepancies.

EDIT: corrected error.