bluescreens and other crashes

XxMX26xX

Honorable
Apr 12, 2013
48
0
10,530
ok, so, lately i'v been getting frequent bluescreens when alt tabing, changing windows or tabs or closing applications (cs:go crashes my PC 70% of the time when exiting), at 1st i thought it was a windows thing because of win32k.sys at bluescreen (and i was too lazy to do something about it), but now i got this: http://youtu.be/hqCYHhSnXaw
the last few days my PC was just randomly changing windows when i alt tabbed, and now it did that after it was done changing windows. My PC has started and is working after i restarted it.
PC specs:
ASrock extreme Z77 mobo
i7 3770k
asus radeon r9 290x dc2oc (installed mid spring this year, and reinstalled windows while at it)
850 W corsair PSU
8 gigs of ram

i also scan my PC weekly for viruses
i have no idea why this is happening, and i'm getting worried now...