Hard Crashes

[d3athwish]

My computer has been crashing randomly while playing video games.  Specifically only Starcraft 2 (just because that's all I play).  The crashes have been becoming more frequent.  Sometimes I get an IRQL_NOT_LESS_OR_EQUAL, but other times, my computer simply restarts on its own.

Even before I overclocked my processor (no voltage increases, just the processor is OC'd), the game would crash.  After I overclocked, I felt like the crashes were less frequent, but lately, I feel that crashes are becoming much more frequent.  Today I experienced four hard crashes.  A couple times I got the BSOD with said "IRQL" error, but the other two I had the computer simply spaz out on me and then restart on its own.  When my computer crashes, the audio loops for a couple seconds while the video becomes a little altered.  The video seems cropped with a black frame.

I don't believe my overclock is what's causing the problem.  I'm afraid this is a GPU problem, or maybe a RAM issue, despite having ran the memory tester on the motherboard and the RAM had no errors.  What's especially strange to me is that when I tried to get rid of my OC settings by selecting the 'Optimal Default Settings' in the bios, my computer wouldn't even finish booting.  I mean I would get to the desktop but the computer would never finish loading programs.  It would simply hard freeze and force me to shut it off.

So I don't know what is the problem.  How can I get started on getting rid of the hard crashes?  Are there any diagnostic tests I can run on my system?

Some specs:
Windows 7 64bit
Norton Security Suite
Biostar TA890FXE
AMD 1055t OC'd to 3.6 with stock voltage
Two Radeon 4850's in Crossfire
4GB 1333MHz (stock speed)
750W PSU

[Jhon Gilly]

I would suggest you to follow a few things in order to avoid the computer crashes
The most common reason for a computer crash is known as hardware conflict. Hardware conflict occurs when two pieces of hardware-a keyboard and mouse, for example-share the same interrupt request channel (IRQ). The simplest way to avoid this is by checking the IRQ's being utilized at a given moment, and then re-installing any device that is using a repeated IRQ.
Random Access Memory or RAM problems could be causing your computer to crash. By mixing RAM chips of different speeds, your computer will be forced to run them all at a lower speed and can hence cause a crash. You can avoid this problem by making sure all the RAM chips installed within your computer are the same speed, or by increasing the wait state of the RAM within the BIOS settings on your computer. 
After a few weeks of use, the information on your hard drive begins to become fragmented. It is an excellent idea to defragment your hard drive every week or so to keep your computer running smooth and fast. 
Fatal VXD Errors and OE Exceptions are typically caused by video card problems. These can usually be fixed quite easily by reducing the resolution of the video display.
Another cause of computer crashes is software that has been installed improperly. The easiest way to fix this problem when you suspect software malfunction is by completely removing the suspect software, then re-installing it.
All central processing units or CPU's generate a lot of heat and are fitted with factory installed cooling apparatus. When the CPU overheats, it causes a crash, which is known as a kernel error. A great investment to remedy this problem is an after market cooling system, or larger fan.
The final problem, which could be causing your computer to crash, is the power supply. An interrupted power supply or surge can wreak havoc on your system. A good idea is investing in an uninterrupted power supply.
I hope you get what you need.
Regards
Jhon

[Allan]

That error message has nothing to do with IRQ assignments. It is generally caused by driver issues. Update all major drivers (video, audio, nic) and check for a bios flash.