I'm running 32bit unstable Debian on a MSI P35 PLATINUM+E8400 with 4GB ram and 169.12 drivers. No problems getting into X, just some hangs while gaming.
My .config has CONFIG_HIGHMEM4G=y and CONFIG_RESOURCES_64BIT=y, which seem like pretty standard options, RedHat/Fedora uses this anyway.. I don't have anything for CONFIG_X86_PAE in my .config, not sure how to enable it otherwise, but I know there's other issues with it so I never bothered.
A few weeks back, several people experienced hangs when attempting to start X and all but one fixed the problem with a BIOS update - http://www.nvnews.net/vbulletin/showthread.php?t=109359
- I don't see anything about memory configuration there, just sounds like most of them were using motherboards that were 1.5-2+ years old.
When I asked for help in the past, a BIOS update was always one of the first things mentioned. If there's something more recent available, you should try it LucidTaZ.