HD5850 "Display driver stopped responding"

I wouldn't do that. TDR is a very useful feature of the OS that allows it to recover from a failure that in previous OS's would have resulted in a bluescreen crash.
The fact that it can't recover using TDR and still goes to bluescreen means that the error is serious.
You've done all the diagnostics: you tested your memory, checked the power supply, cleaned and replaced the drivers, used different drivers. That leaves as the only logical conclusion: your hardware is defective.

The ATI 5850 is a very good, high end video engine that should work well for most current games even without SLI, but the cards are made by different vendors and you can't assume that every card using the 5850 chipset is the same.

Another possibility that I don't recall mentioned: are other people able to play these same games with only one 5850 card without video errors? If you turn the game resolution down, does the problem go away?

No, the games are running smooth with high fps when this happens. The problem still occur if I turn down the resolution or graphic details etc.

I also had this problem with my Nvidia card, replacing it was the only solution

Yeah, I'm getting the idea that that's the only solution to this problem.

At the same time i've read about people replacing their cards and ends up having the same problem.

CptZiggy said:

Yeah, I'm getting the idea that that's the only solution to this problem.

At the same time i've read about people replacing their cards and ends up having the same problem.

Some people solved this issue by adjusting RAM timings and voltage

What should I put the different timings and voltage on?

It's on auto.. I can't find anything in the manual or online.

That would apply to overclockers. Overclocking your RAM or CPU can cause video problems on some systems. If you are overclocking and having video problems you would reset the BIOS to default settings as one of your first diagnostic tests. So the answer to your question is to set the timings and voltages to factory defaults. There will be that option in the BIOS menu, usually on the EXIT tab.

It is also warranted in some cases to upgrade the BIOS to the most current version, particularly if the motherboard manufacturer says that the newer BIOS corrects memory problems.

In my case, neither updating the BIOS nor changing the memory timings to default had any effect on the video problem.

I notice you are using an ASUS motherboad.

It has recently come to my attention that nearly all ASUS motherbords < 3 years old are set to "auto-overclock" and they actually burn themselves out as well as possibly video cards and ram. (As did my wifes computer last week)

If your MB has not fried itself or your video card you can try to go into the bios and turn that off. Unfortuantely that requires KNOWING what your CPU is what it's bus speed and multiplier are suposed to be and the ram bus speed. (i.e. 233mhz, 10x, 1033mhz) Unlike most motherboards where "auto" actually sets everything to safe and same levels for you, "Auto" on Asus attempts to overcolck on every boot and is not helpful about just setting stock settings.

I do not plan on buying any more ASUS motherbords now...

Hey CPTZiggy i have had the same problem for the past month or two and have found nothing to fix the issue, i think i will just have to wait for ati to release drivers to fix this, i believe it is a driver issue. I have same card and also use an asus MoBo. I have tried all combo's of ati/ windows drivers. i have flashed bios and installed all utilities, tried all different clocks. It is definately not a overheating issue. My card runs at 30 degrees under heavy load. I have got my problem mostly taken care of. i only get the driver crash error when i am playing a game usually mass effect 2 or mw2. I run them at max graphics and have no fps issues but i get the error now when i alt tab out and then back in. only happens once and then its all good until i alt+tab again

I sent the card back to the dealer I bought it from, they found nothing wrong with it at all.
I also tried a new PSU, since I had small troubles with the previous one. Same thing happens anyway.

I CAN BELIEVE THIS.

I've purchased 400 dollar GPU I can't use?