Discussion PCI-E 4.0 at 1.1 with FormD 4.0 riser cable

[admirerden]

I need some help from people who maybe enountered this problem already.

I did my latest build recently:

• Asus ROG Strix x570-i Gaming
• Ryzen 9 5900X
• RTX 4080 Founders Edition

It sits in a FormD T1 v2 case with FormD PCI-E 4.0 riser cable. What I noticed that it works perfectly in PCI-E Gen 3 mode, but when I switch to Gen 4 in BIOS, the graphic performance becomes not just worse, but so terrible that it's literally unplayable in most modern games.

Here is what GPU-Z displays for Bus Interface:


Even if I press (?) button and run GPU test, it doesn't switch from 1.1 to anything higher. I updated BIOS firmware on my motherboard to the latest 4602, but it didn't help.
Is FormD PCI-E 4.0 riser cable faulty? Or, what else could be a problem?

 

[rfarmer]

My guess is a faulty riser cable. I know it's a pain but you may want to build the pc outside the case and plug the GPU directly into the motherboard, that way you will know for sure if it is the riser.

 

[SFFMunkee]

Very common with flawed risers to shit out when using signalling rates for PCIe4.0 - sometimes even to the point you can't get to the UEFI/BIOS at all.
Agree with above - if you don't have another known-good riser, try pulling it out completely and try with no riser.

You could also try setting your MB to bifurcate the PCIe slot, you may have better luck with x8 if the failure in the riser happens to be at that end.

 

[admirerden]

My guess is a faulty riser cable. I know it's a pain but you may want to build the pc outside the case and plug the GPU directly into the motherboard, that way you will know for sure if it is the riser.

Very common with flawed risers to shit out when using signalling rates for PCIe4.0 - sometimes even to the point you can't get to the UEFI/BIOS at all.
Agree with above - if you don't have another known-good riser, try pulling it out completely and try with no riser.

You could also try setting your MB to bifurcate the PCIe slot, you may have better luck with x8 if the failure in the riser happens to be at that end.

Thank you. I'll try it without riser cable at all. If it's faulty, should I try Louqe's riser then? Or which one is more reliable than FormD's?

 

[rfarmer]

Thank you. I'll try it without riser cable at all. If it's faulty, should I try Louqe's riser then? Or which one is more reliable than FormD's?

I have the Louqe cable in my Ghost and it works perfectly.

 

[hereforthefeast]

+1 for the Louqe pcie 4 riser instead. I switched to it for my T1 v1.1 as well.