Two places to look would be:
I added my board to the HCL and it works fine, no instability or crashes with the standard Slackware kernels, and it does support your processor:
I did experience some instability after I once built one of the newest kernels, but it was likely that that was caused by me taking out as much as I could and turning on some experimental stuff.
I think P35 chipset mobos are very well supported. So are ICH chipsets of less than or equal to ICH9. I have an ICH9R. My advice is also to stay away from controller manufacturers JMicron, Silicon Image, and Marvel/Yukon because they tend to have either bad drivers or hardware issues. I had a JMicron controller on a Gigabyte board it cause some weird side-effects, until I disabled it in the BIOS.
Hope that helps.