Static, then Freeze on HTPC

My HTPC is unstable. It freezes once every couple days when I leave the tuner on with Live TV (whether TV is off or on). Interestingly, the image is frozen and appears static-y and the Dolby Digital symbol on my receiver flickers on and off. Everything is unresponsive (Ctrl-Alt-Del, Mouse, Remote) and the only solution is to do a hard reset. Processors are at 25% and 42% usage when I have one recording going and I'm watching another channel.

Any suggestions to trouble shooting? Drivers? Components? Temperature?

Thanks!

My system:
* Windows 7 64-bit
* Motherboard: Gigabyte GA-MA785GMT-UD2H
* Processor: AMD Athlon II X2 240 Regor 2.8GHz Dual-Core (ADX240OCGQBOX)
* RAM: OCZ Obsidian 4GB (2 x 2GB) DDR3 1600
* HD: Western Digital Caviar Green 1TB (WD10EADS)
* DVD: LG DVD Burner GH22NS50
* Case: Antec FusionRemote 350 Micro-ATX
* Tuner: AVerMedia AVerTVHD Duet Tuner A188 PCI-e
* Wi-Fi: ASUS WL-138g V2 PCI Wireless Adapter

Sorry for the delay, long work week...

ATI Radeon HD 4200 driver version: 8.6410.0

Catalyst Control Center version: 2009.0730.58.43017

Any suggestions? Where should I focus? Faulty hardware or drivers?

I've read complaints about the RAM, so I'm tempted to return it and try a different brand.

Sorry to revive an ancient post, but wanted to bring closure. I lived with 1-2 reboots per night, finally got sick of it, and fiddled with RAM settings for hours. Ultimately, I found a combination that's been going for 2 weeks without a hitch!

Problem was that my motherboard and RAM weren't immediately compatible. After I updated the GA-MA785GMT-UD2H BIOS with the following details, the OCZ3OB1600LV4GK RAM stopped causing crashes:

> MB Intelligent Tweaker <<br /> Memory Clock: [x5.33] 1066Mhz
System Voltage Control: [Manual]
DDR3 Voltage Control: [+0.100V] 1.700V
CPU NB VID Control: [+0.175V] 1.3500V

>> DRAM Configuration [Enter] <<
DCTs Mode: [Unganged]
DDR3 Timing Items: [Manual]
CAS# latency: [7T]
RAS to CAS R/W Delay: [7T]
Row Precharge Time: [7T]
Minimum RAS Active Time: [24T]