Graphics card no recognised by mobo

[tmc20]

Hi guys,

At really in need of help and hoping to find some answers!

I recently installed a Sapphire HD7870 to my mobo and it is not being recognised in bios or device manager, although the fans are going.

We've tried the card in another machine and it works fine, even when using my new PSU. I've also tried another card on the mobo and that works fine. No idea what to try next - any help would be greatly appreciated!

Tom

 

[bignastyid]

What version of pci-e slot are you using? There has been a few issues with Amd's pci-e 2.1 and 3.0 video cards not working in older pci-e 1.0 slots.

 

[tmc20]

Thanks for the reply.

I'm using a Z77 Extreme4 mobo, which uses PCI 3.0, so I don't think it's that.

 

[Smeg45]

Detailed system specs down to the PSU rail info - ?

 

[tmc20]

Sorry, I'm not sure where to find the rail info - could you advise?

PSU: OCZ ModXStream Pro 700W Modular PSU Single 12V Rail
Mobo: Asrock Z77 Extreme 4
CPU: i53770k
RAM: G.Skill Ripjaws-X F3-12800CL9D-8GBXL
GFX Sapphire 7870

 

[Smeg45]

Specs look fine, did you connect up everything? It looks like the mobo might be a dud. Do you have a spare GPU to test the PCI-E x16 slot?

 

[tmc20]

Yes - I've tested another GFX, which worked without issue, and it is all connected correctly from what I can see (2 6 pins direct from PSU).

This is why I'm confused - GFX works with another mobo. Mobo works with another GFX, but the just don't seem to work together.

Something is definitely wrong, but I don't know whether to RMA the mobo or the GPU!

 

[tmc20]

That's exactly the situation. It's got me very confused.

Also just to be clear I used the same PSU in all tests.

 

[dudewitbow]

So the situation to be clear is:

1. The GPU works on another computer completely fine
2. The Mobo works with a different GPU
3. The GPU in #1 doesnt work on the Mobo in #2


This is a very odd situation.