crossfire problem ?

[Chris Anargyrou]

hello to the community

i just got my 2x 280x's

current config asrock 990fx extream 9
8350
8gb @1866
850w psu


i enabled crossfire in catalyst but when i open gpu-z and select at the bottom the 2nd 280x it says it runs is 4x lane and not 16x
the main card running fine on 16x

i installed the 1st card in the first mobo slot and the 2nd card in the third mobo slot which is supposed to run 16x

any ideas would be gratefull on how to make them run both 16x or both 8x

Thank in advance

[profJim]

Re: crossfire problem ?

Welcome to the forum.

The specifications in your 990FX Extreme motherboard user manual says:

• 4 x PCI Express 2.0 x16 slots
• PCIE1 @ x16 mode;
• PCIE3 @ x4 mode;
• PCIE4/PCIE5: single at x16 (PCIE4) / x8 (PCIE5) or dual at x8/x8 mode

All four of these pci-e slots are electrically (physically) x16 slots, but the only other slot with true x16 bandwidth is pcie4, but only when pcie5 is empty.

Read page 21, 2.4 Expansion Slots (PCI and PCI Express Slots) and look at the PCIE Slot Conigurations table that shows different pcie setups.

From page 23:
2.5.1 Graphics Card Setup
2.5.1.1 Installing Two SLI^TM-Ready Graphics Cards

• Insert one graphics card into PCIE1 slot and the other graphics card to PCIE4 slot.
  Make sure that the cards are properly seated on the slots.

From page 29:
2.6.1 Graphics Card Setup
2.6.1.1 Installing Two CrossFireX^TM-Ready Graphics Cards

• Insert one Radeon graphics card into PCIE1 slot and the other Radeon graphics card to PCIE4 slot.
  Make sure that the cards are properly seated on the slots.

The bottom line is for optimal dual x16 setups, you need to use the pcie1 and pcie4 slots.

Is this setup confusing? Kind of, but not if your read it carefully and understand the slot rules.

[Dimitris Iliopoulos]

Re: crossfire problem ?

Hi,

Did you found a solution?

I have the same problem....

Thanks

Dimitris

[Dimitris Iliopoulos]

Re: crossfire problem ?

Hi it's me again did I you made it work ? I am still trying but nothing......in crossfire mode the one card is almost not working at all.

if any body has any clue please help.


Thanks in advance

Dimitris