How did you conclude that a ram stick was dead?
Try stripping the rig down:
1 ram stick in DIMM 1
1 GPU if your running SLI
try booting.
check drivers if you get bsod.
Updating the bios is always a good idea but DONT DO IT IF YOU DONT HAVE AN UNSTABLE SYSTEM
Check your CPU cooler is seated correct, it may be overheating and auto shutdown.
Check all power leads for a lose connection
That should keep you busy for a bit
ED