Yo man...I have similar issues and I've been reading around for a few hours now and I highly believe it's my RAM. I have my "original RAM" from like 2 years ago in with new RAM I got about 3 months ago, worked fine until 2 days ago.
ONE SINGLE TIME on a boot up a got a blue screen of death for something dealing with MEMORY (RAM). Ever since then I've been getting a frozen computer every 45 minutes to 2 hours of useage (sometimes sooner than 45 minutes). When I go to manually turn off the computer and turn it back on right after, 90% of the time it freezes on boot up , making me have to leave the computer OFF for about 5-10 minutes before it will actually boot up to desktop again.
-ctrl alt del doesn't work
-sometimes before it freezes it gives me a preliminary freeze, a freeze for about 30 seconds and then within minutes it completely freezes
-I haven't ran computer temps and ****, I HAVE run spyware,spybot, avast, adaware, diskcleanup, defrag
-I did computer temperature and other pcu modifications/inspections about a month ago trying to figure out why Warhammer wasn't running (like inspecting computer temperatures and ****)
-That blue screen of death and the fact that I got 2 or 3 year old RAM makes me believe it's my RAM
Even though your computers only 6 months old. **** can go bad. Give your RAM a troubleshoot. I'm tired of messing with computer problems, I'm going to just drop money on hardware and hope it fixes it.