it seems that you're doing things fine by raising the voltage to 2.1 and inputing the timings. are you sure you changed the correct items to reflect in the memory timings? i'm not TOO knowledgeable about this kinda stuff but it seems to me that you're doing things the way it's supposed to be done..
After memtest try lowering your frequency to 400Mhz and voltage to 1.9v. Run the RAM at 800Mhz and bench with 3dmark06 or equivalent. If it does not crash then it's your mobo not being able to handle 2.1v. I had the same exact issue and had to run the Ram at 800Mhz (1.9v) in order to get a stable system.
Thanks everyone for the suggestions and tips. I've been out of town and am coming back tonight. So I'll try everything when I get home and post the results when I figure out what works and what doesn't.
I ran memtest86. If the memory is at 800Mhz, it runs fine. I left it running through the night and in the morning was still running with no errors. But if I set it to 1066Mhz, it fails pretty quickly (test 4 or 5). Tried just setting the clock and leaving everything to auto, tried setting all the parameters (5-5-5-15, double checked the correct items)... Everything ended up in failure.
So right now I'm running it at 800Mhz, and was waiting for a response from Patriot, that just arrived asking me to test the mem modules individually (I only ran memtest with both modules on). I'll do that later tonight and reply...