680i LT Only working at 8x on PCI-E port

My 7950GX2 is only working at 8x bandwidth on a full PCI-E 16x port, there is no option in nvidia control panel or in BIOS to make it 16x.

Does anybody know how I can go about doing this? Thanks.
6 answers Last reply
More about 680i working port
  1. My best guess is that since the 7950gx2 is a dual card in one slot the pci-e is split in 2 so 8x per card....

    What does cpu-z say the speed is at?
    Does the card show up as 2 cards in the device manager? would explain the 8x....
  2. Well no it wouldnt explain it, im pretty sure people have theirs at 16x, the internal one gives the second card 8x bandwidth. Hence the 24x connector.

    CPU-Z is where im getting this from, it shows up as 2 cards in device manager.
  3. It would be nice if you can provide the maker and model of your board.
    Does your board have 3 PCIe x16 slots? If you do and you plugged it to the middle, then
    it will run at x8 mode. If that is the case, plug it to the first PCIe x16 slot and see if it runs at full speed.
  4. Its in my hardware config.

    XFX 680i LT and 7950GX2.

    it ahsnt got an 8x PCI-E slot so I know its not that.
  5. After doing some research on the
    difference between the 680i and the 680i LT.
    The difference between between these 2 boards is
    the 680i uses the 590MCP where as the 680i LT uses the 570MCP.

    The 590MCP lets you run 2 cards at full x16 speed.
    The 570MCP will reduce the speed down to x8 if your running SLI.
    And since your 7950 GX2 is a dual gpu card, maybe that's why it's running at x8
    instead of x16.

    forum topic #1
    forum topic #2
  6. Actually thats not true.

    680i LT is capable of using full 16x bandwidth for both in SLI. But thats besides the point because its ONLY using one slot. The other is on the actual card. It can be used on SLI with boards with only one PCI-E 16x slot.

    SLI board doesn't have much to do with it tbh.
Ask a new question

Read More

Graphics Cards Control Panel Bandwidth PCI Express Graphics