Strange Graphical Crash

[Ponthel]

I am experiencing a crash while playing and have not been able to figure it out. The crash is similar on different video cards, but with some slight differences. With the better cards, the mouse cursor gets scrambled and then the screen goes black a few seconds later, like the monitor has stopped receiving a signal. On a cheaper card, the mouse cursor gets scrambled and the game screen (not the entire monitor) gets distorted and will go black after a few minutes.

The crash occurs anywhere from 10 minutes to 8 hours from starting Everquest. I have reproduced the crash at least 60 times so far and tried everything I can think of to resolve the issue. I have pictures of what the screen looks like when the crash is occurring, but at this moment I do not see a way to post them.

I have reproduced the crash on:
Three different video cards
Multiple hard drives with fresh Windows 7 64-bit and Everquest installs
Both before and after updating MB and GPU drivers
All memory sticks by removing all 4 sticks and using them 1 at a time

I have also tried:
Running the game in all compatibility modes possible
Running the game through WinEq 2.0 in all compatibility modes
Running just one processor in msconfig

Does anyone have any suggestions? My next step is to replace the motherboard, but because local retailers do not carry those anymore, I would really like to exhaust all possibilities before ordering something online. Thanks.