Windows 7 Freezing Regularly

As of yesterday I am getting windows 7 freezes about every hour or two. Freeze as in windows appears locked, can't open programs, change open window etc. No BSODs. I built the system over a year ago and it has been fine until yesterday, no new programs or updates that I am aware of to start causing these issues. I ran Avast full scan and boot scan with no threats and MalwayreBytes as well with no detected issues. After rebooting the system multiple times a couple boots said to insert a boot device, as if it did not recognize the SSD drive but after rebooting again it showed up. So I ran chkdsk which didn't find anything serious as well as Seatools long read test which showed no problems either. Ran memtest through one pass with no errors, haven't tried testing it for a longer period than that though. I've been running performance monitor to see if anything is going on right before crashing but all activity just drops as if flat-lining and I haven't noticed any kind of spike of activity right before. Weird thing was that my system had frozen but it appeared to still be streaming video to the downstairs ps3 (although it may have already completed the transcode before freezing).When frozen CAPS lock has no effect and occasionally the system will move a bit as if it has unfrozen and my mouse clicks show up but nothing happens until I power off and reboot.