Which BIOS version do you have installed?
Gulftown 980x is validated ( http://en.community.dell.com/owners-club/alienware/f/3746/p/19454954/20132595.aspx#20132595 )
Under Historical Drivers, under bios, try to download/install - at your own risk - the "a12" released on 4.09.12 here which is probably a mislabeled a11:
for whatever reason, it isn't on the common downloads page for A-51. A bios update/flash is always a risky business, so, proceed with caution but might be worth a shot/the risk.
Otherwise, remove cpu, check for bent pins on your mthrbrd, reseat, retry, if a dud --> suspect cpu might be the culprit 😞
I don't think the MB socket can be bad if the 920 still works (but not really sure). My guess would be:
1. Motherboard version (I think there are 2 or more). Might explain why it works for only some people.
2. 980x Stepping. When micro-code is added to BIOS to support a CPU, are all CPUs included or only current Steppings?
3. Bad processor. Have you ever seen it work?
I proved the 980x with the A11 or "A12" but the CPU still not work. I can´t see any bent Pins on my Motherboard. In the old Thread there is no solution for this Problem. Anyone with another tip???
Yes i tryed to reset the CMOS Jumper but without success. Still not working. It´s a blue mainboard but i can´t see any Alienware logo. I don´t understand why there is no "Speaker error" or something else, only the Fans are working without any reaction.