Checksum Error is an error loading the BIOS. Try and reflash that BIOS. Warning Will Robinson, Warning!!! If you do not use the exact......................BIOS for that mobo......it will become a frisbee. I would try to update or restore the BIOS on your mobo before you get another.
Noli Nothis Permittere Te Terere!!
EVGA 680i, Dual EVGA 8800GT'S (650/950), 4 gigs OCZ DDR2 1066, Intel Q9450 at 3.8 Ghz, Koolance Water Cooled, Dual Plextor16x DL DVD+/-RW. Dual WD 250gb 16mb Cache Sata 3.0. 3DMark06 score = 19,168.