Originally Posted by kingeliran
i tried to disconnect the sata cables, did not work.
it might actually be the power supply, but could it be that the psu which is 600 fail and still work powering up the bios? or safemode ?
Power supplies usually fail under load. So at idle or low power consumption, you won't see it.
My one failing power supply (not an uncommon symptom either) would just display its issue by the system spontaneously rebooting like the reset switch would be hit, when it was put under load. It should have handled that load, and it would have, if the unit wasn't failing. Power supplies can sometimes cause crashes too.
Unfortunately, the easiest way to test is to swap out the unit and swap in a known good one. Other good options to try if you're having blue screens:
1) Run MemTest86+ for 24 hours on the unit, from bootable USB key. 24 hours is important. I've had a bad memory module that actually took 2-3 days to fail. An hour or two isn't enough.
2) Consider either trying a different set of graphics card drivers or temporarily trying an alternate graphics card (or integrated graphics of the 9900K). You didn't mention what you had, or what its operating temperatures were.
Usually, if you have a CPU problem (rare) it's going to show itself in one of several ways. Temperature issues (yours is showing normal), or in rare cases, I've actually seen a CPU cache fail, but usually the system crashes pretty quick if that's the issue.