PCI Express X8

battery111

Distinguished
Sep 11, 2005
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0
18,510
I am curious, can one use a PCI express X8 card in a pci express X16 slot? I have been looking at raid controllers and all the pci express raid controllers I find are X8, but I can only find X8 slots on server mobos, which I do not want. If I were to get an SLI motherboard, w/ two X16 slots, could I use a video card in one, and an X8 card in the other?
 

Crashman

Polypheme
Former Staff
I put an nVidia card in one slot and an ATI card in the other, no problem so long as I had the "right" card selected as display one. I think it was whichever card was mounted in the top slot. Windows gave me driver crap after rebooting with the wrong card chosen as display 1.

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Crashman

Polypheme
Former Staff
I haven't had any problems running another card in the second slot. You'd get 2 x8 slots rather than 1 x16 with today's boards, but otherwise you'd be fine.

You should also be able to run the card in x1 or x4 mode. Considering x1 is 256MB/s in each direction, x1 is fast enough for a 4-drive array. Anything faster would require more, MSI has a board with all 4 extra pathways tied to an open-ended slot.

The open-ended x4 slot is designed to hold cards like the x8 RAID card. That's why one end was left open. Using the MSI board with the x4 slot, you'd get x16 graphics and 1GB/s via x4 to your x8 RAID card. And 1GB/s is enough for at least 8 of the fastest drives!

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>