just tried again and got code 01 at bootup. "Expand the Xgroup codes locating in the physical address 1000:0" What the heck is that? The 2 codes ive gotten with trying 4Gb today have been 05 and 01. Voltages are MCH 1.44, ICHI 1.65v, Vcore 1.51v, Vdimm 2.2v, CPU Vtt, 2 notches above stock. Timings are all set at 4-4-4-12-42 at DDR2 800 which should be no sweat for them. I did a memtest with all of them last week at over 1000 and they were all fine.

Just tried to boot it again and got code C5. Thats 3 different codes in one day...