Lockup no BSOD

[bdiddytampa]

Been having this problem intermittently since I installed my PC into a new box (Thermaltake New Soprano) about a month ago and I'm stumped. My PC will lockup with no blue screen and there is no pattern that I am aware of. It has happened while watching videos, in my web browser, playing games, and just now while idle. I've tried everything within my knowledge base and it still does it. I've reinstalled Windows 7, checked and rechecked all my connections, the case has good airflow, all the fans work, all of my temps are good, all of my drivers are up to date, I've run diagnostics, malware detection and virus detection deep scans on all of my hard drives, I'm stumped. Not sure where to turn next. Only thing that i did differently was route my cables behind the motherboard when I rebuilt, but I'm not sure how that would effect and cause this kind of crash. So if anyone has any help tips or pointers let me know

These are my components

CPU: i5 2500K was OCd at 4.5 dropped it to 4.0 at 1.2v while I've been troubleshooting
Heatsink: Coolermaster 212 + with push pull corsair quiet SP 120s
Mobo: ASRock Z77 Extreme 4
RAM: G. skill ripjaws 2133 16GB
GPU: MSI GTX 560ti
PSU: OCZ 600w 80 plus cert
Storage: 1 - Crucial M4 128GB SSD, 1 - Seagate Barricuda 1TB, and 1 Seagate Barricuda 3TB

 

[Frisbee_68]

Is your computer fully crashing, like turning off? Or does the screen and sound just lock up, and recover after a minute or so?