I have the same problem from some time (~1 month). I did not change anything in my hardware. Yesterday I did complete format, I double check my RAM with memtest (0 errors), hdd - no bad sectors,
I still have random crash with Error: IRQL_NOT_LESS_OR_EQUAL
Here are the results of my crashes (files in attachment):
Crash dump directory: C:\Windows\Minidump
Crash dumps are enabled on your computer.
On Tue 2014-12-09 06:39:59 GMT your computer crashed
crash dump file: C:\Windows\Minidump\120914-8205-01.dmp
This was probably caused by the following module: ntoskrnl.exe (nt+0x7