When I got home from work today I turned my Windows 7 computer on and got the message "a disk read error occurred" on my Samsung 840 pro. I tried to boot into Windows 10 which is on a different SSD, it got to the log in screen then failed. I tested all the hard drive connections (fine), rebooted to Windows 7 again, checkdisk ran (on a non-OS drive) and it eventually booted fine. W10 runs ok now too.

Slightly disconcerting as I rely on the machine (though I have a backup/laptop). It was probably 33 degrees in my office, but it started fine after a few minutes. Memtest x86 was run a few days ago, no problems.

I'll probably write it off as "one of those things" but interested in hearing thoughts. Computer seems fine now. If anyone knows a good general test suite that could be interesting - I know prime95 but it's fairly limited.