Dark, read the OP again
Master, read the OP again - he'd be upgrading the CPU.
Keep current system with new card:
Core 2 Quad q6600
8 gigs DDR2 RAM
GTX 660 or HD 7850
Or a new board and CPU for SLi:
4 gigs DDR3 1600 RAM
a cheaper MSI Mobo
2x9800 GTX+ via SLi
keep his old arse cpu on lga 775 and get a new gpu or drop the old arse cpu for an i5 and use Sli'd old ass gpu's.
i say do both, but the i5 and 9800's (that he has already) will be good enough for a while, until he gets more green.