Solved Performance difference based on position of single GPU?

[Tomha]

My motherboard has the following PCIe slots for graphics cards:
2 x PCIe 3.0/2.0 x16 (x16 or dual x8)
1 x PCIe 2.0 x16 (x4 mode, black)
I gather the top and middle slots will offer no benefits over each other, but with a single GPU, will I notice a decrease in performance using the last PCIe 2.0 slot rather than one of the PCIe 3.0 slots. Its no real reason, just my graphics card blocks the pretty blue lights on the south bridge and if I moved it down it would block an annoying red light instead

 

[solarmystic]

Hello Tomha,

I reckon you won't see any peformance decrease if you use the PCI-E 2.0 slot as long as it's set to x16, and not x4 as you currently have in your configuration...

Reviews from reputable sites such as HardwareSecrets.com (AMD Radeon HD 7970 Video Card Review | Hardware Secrets) have shown no differences in peformance when the card is plugged into either the PCI-E 2.0 x16 slot or the 3.0 slot for now, and since the 7970 is slightly more likely to saturate the bus as compared to your 7950, you should be good to go.

Hope that helps!

 

[Tomha]

That does indeed help, how though would I change the last slot to 16x? Is that possible or is it a predetermined part of the motherboard?

Thanks.

 

[solarmystic]

You mentioned in your OP that the Last PCI-E slot is at x4 but is capable of x16.

My motherboard has the following PCIe slots for graphics cards:
2 x PCIe 3.0/2.0 x16 (x16 or dual x8)
1 x PCIe 2.0 x16 (x4 mode, black)
I gather the top and middle slots will offer no benefits over each other, but with a single GPU, will I notice a decrease in performance using the last PCIe 2.0 slot rather than one of the PCIe 3.0 slots. Its no real reason, just my graphics card blocks the pretty blue lights on the south bridge and if I moved it down it would block an annoying red light instead

There should be an option in your BIOS that alows you to select the mode of operation for that slot, i reckon. If not, try putting the card in the slot anyway, the mode of operation will change according to the demands of the card in the slot dynamically.

If you want to be sure that you're getting the right mode of PCI-E operation for your card in Windows you can always use GPU-Z to confirm it.

http://www.techpowerup.com/gpuz/



Clicking on the ? next to the interface information will allow you run a render test that will show you the true values of the PCI-E Link speed

 

[Tomha]

Sounds good, Ill have a look. Thanks

 

[solarmystic]

You're most welcome!

 

[Tomha]

I can't find an option, doesn't really matter though, I'll just move it to the middle slot. The annoying light is the Q-Code display or something, the one that tells you what the motherboard is doing. Moving it down one will at least obstruct it a little but still allow me to see it, ill be able to see the perty blue light, no speed decrease, and everyone's happy .

Problem solved, thanks for the help

 

[solarmystic]

Glad to have been of service!