I'm trying to figure out what is wrong with a system and am stumped. The system is an AMD 64X2 5200+ installed in an ASUS M2N32 WS Pro, with 4x1GB RAM & 2x GeForce 8800GTS in SLi, 1 Seagate Barracuda 320 GB on SATA1 and 3 Samsung 500GB Spinpoint T series in JBOD array on SATA2, 4 & 6. All installed in a Thermaltake Armor tower.
The problem began with one of the video cards no longer appearing in the system, and the system having intermittent issues with POSTing (this is a friends PC, so I did not see the problem until it asked to look at it). The video cards were then reseated and the POST error ( 1 long, 2 short) began. Next, each video card was tested alone in the system, without change. Then removed both 8800GTSs and installed a 8500GT from a working system, no change. I then installed the 8800GTSs in the 2nd working system and both tested fine. I then replaced the M2N32 with another spare M2N32 into the system and the system first displayed the same POST error code (1 long, 2 short), but after a reboot, loaded the Bios & OS fine. The new graphic card was detected, but otherwise no changes in the OS. It was left on overnight, and in the morning the monitor was out and would not respond to mouse or keyboard, and after reboot began to display the same POST error code (1 long, 2 short). I have tried the 8500GT in both PCIE slots with the same results, as well as reset the CMOS.
I am about to begin testing the ram one at a time in DIMM_A1, to see if this is the culprit, but would really appreciate any advice. I'm a software guy trying to help a friend with hardware I am unfamiliar with. If I need to post more info, just let me know.