And the plot thickens.  Please see my thread here about my 3d acceleration problems.

When I tested the Direct3d and Directdraw capabilities through DXDiag, it was before I had played OFP and it had crashed and given me the error message (when I tried to start it again).  Well, by pure luck, I decided to test it again after it crashed and gave me the message a few minutes ago.  What I found was

Before:

DirectDraw Accelration                 Enabled
Direct3d Accleration                         Enabled
AGP Texture Acceleration             Enabled

After OFP:

DirectDraw Accelration                 Enabled
Direct3d Accleration                         Enabled
AGP Texture Acceleration             Not Available

And it gets better.  When I tested functionality before, everything was 100% aok.  When I tested it after OFP, DirectDraw was fine, and Direct3d didn't work-it said it failed in step 8, where it creates the 3d drivers (or something like that) for all three tests.

When I reboot, all this rights itself.  My computer guru hasn't called back yet, and I can't make heads or tails of this.  The only conclusion that I can come to is that I used to think that it was a hardware problem-it now appears to be a software problem with OFP.  It does something to my vid card.  A reinstall of OFP has been long overdo-is there anything else that this all might mean?

Ok, as it turned out, it was an overheating problem.  Playing with the side of the case off has seemed to fix it (I hope, I did a reinstall+reg cleaner and it's been running strong for 5 minutes, no hiccups).  I didn't pick it up as an overheating problem because all my other games have been fine, and it's never been a problem with OFP.  Thanks for all your help Weather_Man.

EDIT: Nevermind.