I just changed RAM slots and changed headers around and changed Mains power connecctor, this time it is in a boot loop (i.e. boots I see number 55 on the 2 digit display on the mobo, stays alive for about 15 seconds and all fans are spinning), I dont see anything on monitor display, but that could be something to do with using HDMI, the MOBO has no VGA/DVI port.
Could it be the 3GHz RAM sticks?
Edit: Also tried removing one RAM, also tried putting one RAM stick in another slot. Also tried both sticks in both slots again.
Even tried no RAM, all result in LED Debug Code 55
Only thing I can think of is to try reseating the CPU.