This just started this week, no new hardware, no major updates or software installs either before it started happening. The system will often start slowing down or hang completely before BSOD, and there doesn't seem to be any pattern of when it happens.
Either comes up as KERNEL_DATA_INPAGE_ERROR, or simply says "A process or thread crucial to system operation has unexpectedly exited or been terminated."
Searched around for issues, tried a lot of the common fixes - updated drivers, updated firmware on my harddrive since a lot of topics suggested that may be the problem, ran chkdsk didn't find any problems.
Here are pics of some of the many BSODs I've gotten:

Is this a hardware or software issue? And how can I pinpoint which device or program is causing the problem?