I have three identical cases, with three simular motherboards (asus p5phl) and three simular cpu's lga775. All populated simularily w/ sata dvd-rom and harddrives.
Two installed easily. Third refused to install. Randomly, but typically during the format during install, the computer would totally freeze, w/o warning. I checked everything.
Ram test, cpu test, drive tests, swapped motherboard, cpu , drives, powersupply. But nothing worked. Finally, I tried swapping the ram (2 GB) with a ram stick in a working computer (1 GB). Now it works perfectly.
I can see no difference in either Ram, other than the size. The motherboard is good for 4 GB over two slots. And the (defective) ram is working just fine in the other motherboard. Why? Who knows... This leads me to conclude:
1) Printed specifications are maybees:
2) Software tests are maybees.
3) Swapping is the only true test.
4) Just because it doesn't work, doesn't mean it's broken...
p.s. Three weeks (parttime) I wasted getting it working.
memtest86 or it did not happen.
Three identical systems. 2 work, one doesn't. Preponderance of evidence is that there is a hardware problem with the motherboard (most likely). If manufacturer doesn't have a thorough system test program to run, then send it back for replacement.
Did you stick the ram in the second slot of the PC that works?
If so try swapping them round to see if it still works