I'm having a similar (if not identical) problem. Upgraded to 8.10 from 8.04. After upgrade, computer will lockup at random times (anywhere from 30 seconds after login window appears, or up to 30 minutes of web browsing, music, etc). Tried removing compiz. Done sever apt-get update, apt-get upgrades from the recovery console. Tried the above trick of specifing pci-e in the bios.
I also tried installing linux-backports-modules-intrepid and linux-backports-modules-intrepid-generic. I don't know what they do, but they didn't fix anything.
Running a nVidia card with nVdida drivers that worked fine in 8.04.
Let me know what other information I can post or anything else I could try.
Thanks!
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