Interestingly, I have this same board (ASUS M4A785TD-V EVO) with a Phenom II X3 (basically the same CPU with one core disabled). I have 4gb of G.SKILL "Ripjaws" DDR3, and a Powercolor 4770 (interesting, same manufacturer there too). The motherboard is flashed to the newest BIOS, running Windows 7 Ultimate x64. No antivirus currently installed.
I have similar issues, though my BSODs seem to be more random. Sometimes they're in "Memory Management", other times it says a program is trying to write to read-only memory.
At first I thought it was the Realtek network adapter driver, so I removed it and ran the driver that came with Windows 7. No change.
I wiped the hard drive and reinstalled Windows 7 from scratch, as I was running on the same install as before I swapped the motherboard/CPU/etc. Same issue.
I thought it was a buggy Via sound driver. Removed it, went back to the Windows 7 default driver, same issue.
I ran Prime95 on it for 3-4 hours, no failures.
I ran Memtest86+ v.4.0 off one of my SuSE Linux 11.2 x64 install disks. When I left for work this morning it had hit 7.5 hours running with no errors, I left it running to be sure.
I suspect it's either a buggy ATI Radeon driver or a buggy Realtek network adapter driver, but I can't be sure. I've been tempted to order a standalone NIC with a chipset from another manufacturer, as it seems to happen when there's a lot of network activity. I'll be extracting a large RAR file stored on my Linux box and it will crash, or I'll be watching a HD movie stored on the server and it will crash. I've tried to make it crash by extracting RAR files while watching movies while running Prime95, and nothing. It's totally random.
I'm about ready to dump Win7 64bit off and go back to 32bit. I really suspect it's a poor 64bit driver as manufacturers are still dragging their feet on writing decent x64 drivers.
I can upload my memory dump files if anyone wants to take a look.
MattB