two 1gig sticks, one 2gig stick all at 667, a 9600gt 512, 5400+ dual core, ga-m57sli-s4 mobo, 800watt psu
Could be a BIOS glitch, check for a newer BIOS depending on the board revision:Rev. 1.0 and 1.1 use the same BIOSRev. 2.0 uses a different BIOS
Although the AMD64 memory controller is flexible enough to run an odd-ball memory configuration like you have (single channel mode only), it does pose more work for BIOS programmers beyond the more common and recommended memory configurations. Because it poses more work, odd-ball memory configurations tend to be a weak spot in BIOS programming. If a BIOS update doesn't solve it (or you already have the latest BIOS), find another 2GB module to test so that each channel is matched.