- update: no RAM failure, two more minidump files -
Well, MemTest86+ does not show errors after 9 passes, so I guess it's not the RAM.
I have uploaded two more minidump files with this post of the most recent crashes. (Firefox crashes every time I start to play a YouTube video.) BlueScreenView identifies the culprits in these dumps as HIDPARSE.SYS (the Firefox/YouTube crash) and volmgr.sys. The driver from the first dump was ntoskrnl.exe. I guess that's to general to arrive at any conclusions?
I should try Driver Verifier next then.