Screen freezes, sound grinds noise at me, and computer locks up

Not entirely sure what is causing this but I almost thing it's my GPU.

System specs:

ASUS M4A89GTD PRO/USB3
AMD Phenom II x4 955 BE
2x HIS HD 7970 IceQ
16GB Corsair Dominator RAM 1600
Crucial M4 128GB SSD
2x 1TB Western Digital Caviar Black HDDs @7200rpm

As of last night, every hour (minimum) to every few hours, my screens will lock up, and sound grinds up.

I'm currently running 2 monitors. The secondary monitor just freezes. The primary either A. Goes black, and turns itself off, or B. Becomes all Black + White vertical bars, and eventually turns off. The sound seems to be a constant loop of the last sound played before the crash, but it sounds like a dial up modem screaming at me. Eventually I have to hard reboot.

I've tried using drive sweeper to remove all traces of the original GPU drivers, and updated to the newest drivers (they were outdated by 1 version), but that didn't help.
I have also made sure my SSD is up to date on it's firmware, because my computer was having crashes every 45 minutes less than 2 months ago because it needed a fix added in a more recent version of firmware.
When I did the SSD fix, I ran multiple passes of MemTest86 on each stick of RAM, individually. I'd hate to have to go through that again, but if it's a possible culprit, then I might have to.

When the computer froze and crashed last, I had CPUID HW Monitor open on my second monitor; none of my hardware was running abnormally (that I could tell), and nothing was overheating or even close to running hot.


The problem seems to occur more quickly when I apply more stress to the system. But even just being idle, it will crash eventually. It crashed just minutes after starting up Planetside 2, and about 30 minutes after starting APB. Without playing games on fresh start ups, playing music + browsing multiple tabs in chrome, and watching videos on YouTube also sped up the process.


Any help? ._.