well well well pci 3

froller2

Honorable
Oct 29, 2013
442
0
10,790
so today i got my radeon 7970, and as i was putting it in my mobo i couldnt get it to show on the screen... took me around 40mins fooling around with my pc til i tried the pci 2.0 slot i had then it worked...
my mobo is a asrock z77 pro3 the pci 3 worked fine with a 680 last night but today it wouldnt work witha 7970..=?
and is there any big performance lose using a pci2 over a pci3 ?
 
Overall there is very little performance loss with a PCIe 2.0 x16 over a PCIe 3.0 x16. I don't see that that lane is a full x16 PCIe 2.0 though which would have performance loss.

The HD7970 does support PCIe 3.0, I have mine in a Asus Maximus VI Formula which is PCIe 3.0.

Which CPU do you have?

*Update*

Look at this:

asrock-z77-pro3-layout-5.jpg


That's is a picture of the slots. The second slot is a PCIe 2.0 but only supports up to x4 which means it will lower performance a bit. I would say try the PCIe 3.0 slot again and see if in the BIOS you can turn on integrated graphics.

What I find weird is that they didn't use the PCIe 3.0 to its fullest which is normally to have 2 PCIe 3.0 x16 slots with it being able to drop to X8/X8 when in SLI or CFX mode.
 


ohh ok thanks bud
 


intel core i5 3570k
 


well tried, didnt work, read from various sites that other people with the same mobo is having the pci3 problem when it comes to radeon cards... so il have to get another mobo as i want crossfire

 


My honest suggestion is a Asus. I have never had an issue with them. One problem is that you have a older CPU, a Ivy Bridge, and they are being phased out.

http://www.newegg.com/Product/Product.aspx?Item=N82E16813131819

That might be the best one you can get for LGA1155.