Boot problem with Gigabyte AB-350 GAMING 3 and Gigabyte GTX 970 G1 Gaming

[Konterbier]

Hello Community,
I recently upgraded my PC with a new Ryzen 5 1600 processor and a fitting mainboard as well as new RAM. My new Gigabyte mainboard seems to have a problem with my old graphics card (which worked just fine with my old mobo) though. Seemingly random the mainboard fails to initialize/recognize my graphics card and I get no video output. Not even BIOS/UEFI. I cannot reproduce it. To regain a video signal i have to restart/reset several times until I get a video signal. From there on everything works just fine. Driver installed, performance is as usual.
Bios is updated to it´s latest version and graphic card´s drivers are fresh too.
Any idea what this could be?

 

[cin19]

What memory do you have?
Also how the PSU too?

One more thing, do you try update the newer BIOS yet? it came out 4/10/2017. I think it will help you solve the problem. http://www.gigabyte.us/Motherboard/GA-AB350-Gaming-3-rev-10#support-dl

 

[Konterbier]

RAM: Corsair Vengeance LPX 8GB (CMK8GX4M1A2666C16R)
I ordered a new PSU already, my current one is pretty old (2009). It will arrive tomorrow and i will report back.
Funny thing is: I put in my old graphics card and it boots up just fine...

 

[cin19]

Looks like the problem maybe from the PSU, because you can use the old GPU. So if the gtx970 is more powerful than the old GPU, and the problem is the PSU.

 

[Konterbier]

Great. PSU I ordered was defective, waiting for a new one . Funny thing is: my GTX 970 worked just fine with my current PSU and old mobo.

 

[sajmon83]

The funny thing is that I have an identical graphics card and identical motherboard and I have the same problem. Dot to dot as the friend described above. So the problem lies in the motherboard I think so.

 

[vapour]

what old graphic card do you have?

 

[sajmon83]

MSI GeForce GTX 970 OC

 

[vapour]

Thought that is the old one... What is the new gpu and old PSU?

 

[Konterbier]

It´s not the Mobo. I tried another Mobo with the GPU and it still wouldnt boot. It´s the GPU that doesn´t seem to work with Ryzen. try placing the GPU in a PCIe x4 slot and you will see it will work just fine. That´s because the PCIe x4 Lanes go overr the Mainboard chip and after that to the CPU. If the GPU is in the PCIe x16 slot it´s directly connected to the CPU and it wont work. I fixed the problem by selling my old GPU and getting a new one. Bam works.