Rampage II extreme kept restarting now won't power up

[suggdozer]

Help, trying to a diagnose a problem to see if it is my RAM or mobo that is broke. I use an i7 980x with a noctua nh-up12 cooler, rampage II extreme mobo with 6gb 1600mhz corsair dominator. Machine has been running for over 2 years, used an i7 920 for a year before i got the 980x. Problem started ; few days where my computer would restart itself or shutdown mid session, this kept recurring til I restarted the bios via the CMOS and set settings from my custom overclock config to defaults. Cpu was oc'd to 4.0ghz. Though even after downclocking the comp to stock settings it did keep on restarting itself a couple of times - once during windows startup repair and during windows memory test. I did manage to run memtest86+ which got 0 passes and over 400 thousand errors on test 7. Cpu temp seemed normal at around low to mid 30's checked using real temp, ram seemed hot for stock temps as was displaying 51c in bios. Got to the point now where comp won't start even when i reset the CMOS, i've tried turning the pc on with no ram in and it won't start just displays welcome on lcd poster and the timer, a fan also may spin - same as what it would do occasionally in between the system booting before it would eventually restart . I've ordered some new ram in case that was the problem but I fear it may still be a motherboard problem.

 

[suggdozer]

replaced the ram and still won't start. I'm now blaming the psu or motherboard, anyway i can check without buying new components.