Re: GZ-Z77X-UD5H Random freezing and shutdowns.
Update to the latest audio drivers for your motherboard. Plus try to disable the deeper C-States (C3/C6/C7) and see if this works. As you describe it the freezes appear on light load or idle. I had the same problem with my new SSD in a system that was working with C-States enabled for over 2 years.
Intel Core i5-750 @ 3.6 Ghz 1.18V| Gigabyte P55-USB3 Rev. 2.0 | Kingston KHX 4GB DDR3 @ 1440 CL7 | Gainward Gtx 460 GS 1GB | Intel 330 120GB SSD | Seagate Barracuda 1TB | Chieftec Gaming Series 500W 80+ | Thermaltake WingRS 100 Piano Black