Serious Driver/Hardware compatibility problem

Well I am at my wits end and have done everything I can think of to troubleshoot this issue and I still cannot pinpoint it. I am a network admin and I work with faulty hardware all day long, but this problem is just ridiculous.

My Specs:
Soyo KT-600 Plus 1.0 mainboard
Athlon XP 3200+
1 Gig PMI Turbo memory with heatsinks
ATI x1600 Pro 512MB AGP video card
Creative Audigy2 Platinum Pro sound card
Western Digital 120GB SATA drive
Aerocool 550 Watt PSU

The problem:
My problem only occurs when running graphics-intensive games including: BF2, Hitman Blood Money and Ghost Recon Advanced Warfighter. The only game I can currently play without any problems is COD2, which I'm guessing is because it doesnt tax my system as much as the others do. Specifically, BF2 and GR crash to the desktop during gameplay in SP and MP modes. Hitman is the worst offender. It gives me this BSOD:

IRQL_NOT_LESS_OR_EQUAL

and the technical info is

***STOP: 0x0000000A (0xFFFE8080, 0x00000002, 0x00000001 0x806EE2DC)

Now I've searched hi and low to troubleshoot this particular stop error, but have not found any of the solutions on the net to solve my problem. I have tested just about every piece of hardware in my machine, and I have reinstalled windows and all drivers. I know the first thing most of you will say is that this error requires new memory or a video card change. Well I've done about 12 passes on my memory with memtest with no errors, and my current video card is a brand new one only a week old. I used to have an ATI Radeon 9600XT and thought it was fried, so I bought the new one. But the problem is not because of the video card itself.

But here is one issue that leads me to believe that ATI's drivers are conflicting with my mainboard. The only set of drivers that seem to work with my hardware is the Catalyst 6.3 drivers. I've tried every other Catalyst 6.x driver, and this is the only one that works well. For instance, if I try to install the newest Catalyst 6.5 drivers, Windows all of sudden performs terribly. Half of the icons do not show up on the desktop, everything is very choppy, the color profile seems to be faulty and most of the colors are not displayed. Basically the drivers are useless even though this is a brand new high end ATI video card. Btw, my old card committed these same crimes with ATI drivers. So because of that issue, I am assuming that my mainboard does not like these ATI drivers. I've got my VIA chipset upgraded to the latest Hyperion drivers as well to no avail. I am ready to go buy a new motherboard to see if that solves my problem, but figured I would post this here to see if any else had a suggestion.

Thanks for your help!

 

I used to get this error on two computers all the time. Neither have an ati card, I even bought new crucial ram for one of the computers but I still got it.
Both of the computers have a SiS chipset, that is the only hardware similarity. Oh, they both have a cheapo PSU.

Like I said I used to get it, neither comp has had this blue screen for months. I haven't really bothered trying to suss it out, I cant even think of a program which both computers have..... Quatrro Pro and MathCAD. Thats its.

 

When exactly did you get this error? What applications were you running? And it just all of sudden dissapeared?

 

IRQL_NOT_LESS_OR_EQUAL its probably a problem with the RAM, firstly try reseating it and then replace it, you could also run memtest86 on it, run memtest for a few hours

 

If you read my post I clearly stated that I ran memtest for 12 passes and it found no errors.

From my research, the IRQ error more often that not is a device driver conflict and not a problem with the memory. I've read of too many cases where the memory had nothing to do with it. Besides that I've already run memtest thoroughly.

 

sorry, i do skim read a lot, i'll have another look at it

EDIT: i couldn't find much on the net, sorry

 

I used to get it all of a sudden.
Check the irq's in bios but I dont think that was my problem.

 

You receive a "DRIVER_IRQL_NOT_LESS_OR_EQUAL STOP 0xD1" error message, and your Windows NT 4.0-based computer stops responding
Not read it yet, gonna miss the post!!