Question Weird compatibility issue

[manto98]

Good afternoon,
First of all thank you for your time.
A quick background on what's happening.
After some years i decided to upgrade my old system with new parts, in particular:
B760 aorus ddr5 ATX
13600kf ( order CPU, came with nearly 3 weeks of delay, yikes)
Ram Kingston 6000 MHz 2x16
After a quick clean of my old case i pulled out the old hardware and installed the new.
For context: I'm keeping my old 580x ROG strix GPU (1x 8 connector) and my 700w zalman PSU.
Long story short i turn on the PC and i get no video signal.
I checked the status led: CPU and RAM check where ok, but the GPU/vga light was on.
What i tried:

• Checking all the connectors, unplugging and plugging the connectors: it doesn't work
• Plugging my GPU back to my old system: it works
• Taking out the video card and replacing with an even older video card, but more power hungry (2x 8pin connector): it works even though the older video card is broken and cannot be used (artifacts and instability)
• Resetting the bios: it doesn't work
• Removing the cmos battery: it doesn't work
• Hard reset with the jump pin: it doesn't work
• Tried with another PSU of much higher quality (seasonic gold): it doesn't work

The weird part in all of this is that the system seems to work with the older broken card, i checked in the bios and it seems that CPU, ram and SSD are all working correctly. I even managed to install windows.
The newer GPU is working on my old system but not on the newer one.
The only thing that i've yet to try is to flash a new bios on the new Mobo, but I'd rather not.
Does anyone has any idea on what can I try to fix this mess?

Thanks

 

[slavi_asenov2002]

Try putting the card in a different PCI-e slot. Try using different 8 pin cable/change the cable header.
But from what it sounds it could be something that have happened while pulling the cable when cleaning and the 2 suggestions above would be useless. Maybe damaged 8-pin connector on the GPU?
You could also disassemble the GPU and check if there are any burned spots from some kind of shortage as well.

 

[Lucky_SLS]

This might be due to the mobo bios defaulting to pcie 4.0 for the first slot X16 lane.

This is where the non-f cpu would have come in handy...


Do you have a friend with pcie 4.0 gpu for quick trouble shooting?

 

[manto98]

Yes I do have the older card, which is working (kind of)

This one use 2 x 8 pin connectors, i can access the bios with it

But the thing that left me kind of confused is that the other card

With the same PSU and the same PCI connector is also working on an older mobo

But the black card on the new mobo does not pass the initial hardware check and it stay stuck to the vga check with no video signal.
I did not smell burning yesterday, and the connector looks all good.
I belive it's some kind of bios software issue, I'll try to flash the bios and see if I fix it.
I also wrote to the gigabyte support but they have yet to reply.
Again, thanks for you help

Update: flashing the bios, resetted again the bios, and forcing the pci to gen 3 did nothing.
I'll be trying with another gpu this afternoon.

 

[manto98]

Update: after 2 days of troubleshooting i managed to fix it.
Basically my GPU bios firmware was causing problem because of its UEFI/legacy hybrid nature.
I don't know why but downgrading it to an earlier version solved he issue.
The more you know...