Sean (11:55 AM) : If it continues to be unstable then only idea I hve is that one of the memory modules is not seeted properly, or was damaged durring upgrade. ... Me (11:56 AM) : I think your guess is probably good. We should continuously check the status of tiger503. Sean (11:56 AM) : ok...I will. If it goes down again I will remove the new 4 sticks of RAM and see if it will run stable with the original 4. Sean (11:57 AM) : If so, I will take RAM to tester and replace bad module. Me (11:58 AM) : Ok, thank you. I will check tiger503 status carefully.