Re: Computer freezes, but only when it has been turned off.
Use this to test the memory
Memtest86+ - Advanced Memory Diagnostic Tool
And this will give you a masic indication of the hard drive health by getting the SMART info.
HD Tune website
FX-8350 @ 4.7 cooled by H80, 32GB Mushkin Enhanced Blackline 2133, Asus Sabertooth 990FX, 2x Radeon HD 7850 2GB in X-fire, 500GB Samsung 850 Evo, 4TB Seagate, 3TB WD Black, 2x 1TB WD RED in RAID 0