A79A-S purchase with 2 x 9800GTX....O.o

In an attempt to build a new gaming computer, i may have made at least one BIG mistake. I'm hoping you guys can help. Purchased:

Foxconn A79-S 790FX/SB750 MB (with Crossfire support...)
AMD Phenom X4 9950
2 x 2g OCZ Reaper 1066 ram
Velociraptor, SB XGF Pro, etc., etc.
and the kicker.....2 x XFX GeForce 9800GTX Black Edition VCs

I'm a newbie and I think I may have shot myself in the foot. I have the build almost complete when it dawned on me that this MB may not support SLI (please don't flame me, it says nowhere that it DOESN'T).

The only way I could install both cards was top and bottom PCI-E slots (one blue, one black). I read somewhere that blue is x16 and black is x8. That leads me to believe i really screwed up.

If i did, would i be better served buying a new MB or just keeping one VC in the current setup and putting the other in my other computer (replacing 2 x 8800GTX) and using the 2 8800s to build my wife a comp?

or quit building them altogether until I learn WTH i'm doing?

Crossfire only...I would return the cards or the board and get something that is designed to work together. IE 4870's or a SLI motherboard

Geez, I really did screw up this time. I guess it would be cheaper to replace the MB but easier to replace the VCs.

http://www.newegg.com/Product/Product.aspx?Item=N82E16814121269

I guess one of these to start? How would this compare to 2 x 9800GTXs?

If you already have it all built and windows installed then videocards are easier. One 4870x2 should be better than the 9800gtx's. I'd stay with the board you have and change out the card(s)

Treepeeper said:

Geez, I really did screw up this time. I guess it would be cheaper to replace the MB but easier to replace the VCs.

http://www.newegg.com/Product/Product.aspx?Item=N82E16814121269

I guess one of these to start? How would this compare to 2 x 9800GTXs?

Click to expand...

The 4870X2 will outperform the 9800GTX's even, SLI'd the 9800GTX's would be beaten hands down by the 4870X2.

Definitely be the way to go IMO, and much better than replacing the mobo for a Nvidia chipset for SLI. you can always add a 4870 to that 4870X2 as well for Crossfire-X should you want to.....

About installing, if you do get a 2nd card for Crossfire, make sure you install the primary card in the top PCI-E slot, and that the second card is in the correct corresponding PCI-E slot, and that the slots are configured correctly in the BIOS, seems that a lot of BIOS' default to the older standard of PCI-E (PCI-E 1.0) rather than the newer PCI-E 2.0 this is referred to in most BIOS' as "Gen 2.0" so make sure that you have the PCI-E slots configured as Gen 2.0 and at x16 link width, for best performance....

Good Luck....

I appreciate the responses. I went ahead and ordered the 4870x2.

Tips concerning PCI-E slots, bios config, noted.

Thanks!