Hi
Your dxdiag showed no directx problems, so I think that kinda points to a heat or psu related issue. Of course, dxdiag tests d3d only, so only applies to d3d games, and the parts of directx that opengl games use. Dxdiag hardly stresses the system though, so generating enough heat, or stressing the psu like a game does is out of the question. Some ati owners have found relief from crashes by increasing the cooling in the system, putting more fans inside the case, and hopefully directing some airflow to the grafix card. Some have replaced the hsf on the card with a better cooling unit. I added a solid copper hsf from a 1u server system to my 9700, it's low profile so it wouldn't take up the first pci slot. Speaking of pci slots, if you can move all the pci cards away from the vid card, you should get better cooling.This and ram sinks have allowed me to oc the card from 310/325 to 344/351 core and mem, as an example. Not much of an oc but absolutely stable, even with no volt mod to the card. By the way, I have found the 5.7 cats to be the best driver for my 9700 so far.
RMA means Return of Merchandise Authorization. You contact the maker and tell them your card is fooched, they tell you to send it to them for replacement, if they believe you. And if you have a valid warranty.
As well, have you updated your mobo driver?
Some thoughts for you.