Unable to boot to BIOS unless gpu is reseated

Hey guys

I've had this persisting issue with this particular build since I got the i7, the mobo and the ram.
The GPU and the PSU have been used in previous builds with absolutely zero issues.

This issue has stopped and started over several months, starting when the build was first completed.
It seems that, whenever I add a new HDD, or change anything hardware wise after completing the work I am unable to boot to BIOS.
Previously I was resetting the CMOS and leaving it over night and it normally would come right.

Once the pc does get past the BIOS, I won't have an issue for months, unless I change any hardware.

Until tonight when I had found that my RAM was not running on XMP profile to get the correct speed, so I went into the BIOS, selected profile 1, everything else auto and saved and restarted.

The pc would post absolutely fine and everything including the graphics card whirrs up fine but the screen is blank.

After deciding to pull all the components out and reseating, I found that when the GPU was reseated I got a display, but I when I tried to enable this XMP profile, I would be back at the black screen with no BIOS or anything, until I reseat the GPU again.

I have managed to get the pc "working" again, but reseating the gpu and loading optimized default BIOS settings, but I am concerned as to why it is doing it and if there may be something that is potentially faulty.

As explained above the GPU and PSU have both been used on previous builds with no issues like this at all, so I don't believe it could be either (I could be wrong though) and I don't get any ram errors at post either.



Any form of help would be greatly appreciated :)


PC Specs
CPU - Intel i7 6700k

Motherboard - Gigabyte gigabyte z170x-ud3 ultra - F22 latest BIOS firmware

RAM - 2X DDR4 8GB Ballistic 2400 mhz

GPU - EVGA GTX 970 FTW

PSU - 750w Cooler Master

Hi EdTittel

Thanks for your quick response!
I believe it is probably the motherboard also, i just wanted to check that there wasn't anything else maybe that could cause such an issue.
I will try to return the motherboard in the next few days (have to take it back to the distributor here in NZ, which is painful).
I will repost on here when after speaking with them, unless someone has some sort of black magic to make it all magically work!
(:

So I haven't managed to return my Motherboard yet, though I did purchase another (Gigabyte branded) GTX 970 for my HTPC. I tested the new Gigabyte Branded GTX 970 GPU in the above PC and I haven't been able to recreate the same fault. Therefore I believe that this may actually be an issue with the original EVGA GTX 970, I do find this quite strange as it was working perfectly fine up until it was installed on the PC described above. I will be taking the GPU (EVGA GTX 970) into the local store I purchased it from tomorrow for them to test and hopefully cover under warranty, I will update this thread further when I get a response from the local store if anyone cares to read (:

Hey Guys, so I have tested the original 970 in another PC and I can't seem to fault it at all, with all the same functions I was doing on my other PC, so im not really sure whats happened at all haha. Though I guess it's kind of solved??
Thanks for all responses (: