Hello, unsure how to submit this, but:
Here's a fix that worked for me--an uncommon one that, if needed, is the ONLY fix that DID work. Bought Win 7 Ultimate 32 bit. Installed, and everything worked fine--WITHOUT having to use special drivers! Including the mobo chipset drivers. And that was the problem with ONLY Black Ops! Of course I read everything there was available, and even tried the hair-brained ideas submitted by ppl who wanted to help, but had not done any research.
Well, to get to the point, all I did as a last thing, having all the other "try this--" suggestions exhausted, was to install the latest mobo drivers from my Mfgr., which of course replaced those of Microsoft. Even the original mobo disk would have been more appropriate for my system. Which has been upgraded from a core 2Duo to a Quad core q9650, and from 2 GTX260SSC in SLI, to 2 GTX560Ti in SLI. Finally, since the beginning of Win 7, and then Black Ops--I have no more crashes!
This may not be YOUR solution, but it was for me. If Win 7 made you think that you could do without the hardware drivers for the mobo--well, it ain't always so! Good luck on your particular issues. But don't neglect these facts, as I had.