PCIe Bandwidth issues.. Showing x8 width on a single x16 slot

[JamesDodds]

Hey guys,

I have a Gigabyte GA-ma79x-ud4 motherboard, a 6400+ dual core, and a Geforce 260 (192 stream processors). When I bring up Cpuz or Gpuz and look at the graphics bandwidth it says its running in x8 mode instead of x16 on 2.0. The quote from GPUz is
"Bus Interface: PCI-E 2.0 x 16 @ x8 2.0. I am sure you have seen things like this before, but I just need some help. The video card works fine, plays BFBC2, cod, etc, but I want to get everything out of it. Any feed back would be appreciated.

 

[jerreece]

Switching from x8 to x16 on that GTX 260 probably won't make any noticeable difference. However, you might look into your BIOS settings and make sure there is not a setting that's forcing your PCI-E slot to run x8. You could also try updating to the latest driver versions for your GPU and motherboard chipset to be sure there's no updates needed there. (could also check for BIOS updates)

Do you have another graphics card installed on a second GPU slot? (For instance, a second card for PhysX?)

Is this your motherboard?

GA-MA490X-UD4
http://www.gigabyte.us/Products/Motherboard/Products_Overview.aspx?ProductID=3003

This motherboard has two PCI-E GPU lanes. One runs at 16x, and the other runs at x8. So if you have your GPU in the second lane, it will only run at 8x.

The x16 lane is the one closest to the CPU.

 

[JamesDodds]

Hey thanks man for the response. No, I've only got one GPU, no physX card or anything like that. Ive got the GTX 260 in the orange slot for 2.0 x 16, but it only shows in x8 mode. There is a bios setting under andvanced Bios Features called Int Display that is auto set to PCIE, I think, or just PCI, and the other options are PEG or PEG1 and I figured I wasn't Crossfireing so I didn't need to change it. I haven't done a bios flash because I heard they were risky. I mean, I'm gonna flash when I upgrade processors, but that'll be like a year. Any more advice. I appreciate it. (below is a quote from the manual about Xfire.) I have the latest video drivers from windows update. But I can check Nvidia again. GPUz says bios version 62.00.1A.00.60

Before configuring your system for CrossFireX, make sure to set Init Display First under Advanced BIOS
Features in BIOS Setup to PEG first. (Start your system with a single PCIe x16 graphics card and then go
to BIOS Setup to set Init Display First to PEG. Then install the second graphics card to enable CrossFire.)

 

[bystander]

I've had this issue before. Everytime it was a result of the card not being seated well, or dirt in the slot. Some compressed air helped me out the last time.

 

[JamesDodds]

Okay, I'll give that a shot and see what I get. I appreciate the thought.

 

[JamesDodds]

Hey, that did the trick. Checked on Cpuz and Gpuz and the bandwidth now shows up at x16. I just pulled the card out, brushed the slot with a paintbrush, and reinserted. Screwed it down, booted up, and its running at x16. Thanks a million guys.