Looking to step up to a Q9450 for video editing with Sony Vegas. Want stability, so not really gung-ho to overclock, or if I do it won't be significant. Mainly want to take advantage of Sony Vegas's 64-bit version when it comes out for Vista 64. As I understand it, it's important to be able to install lots and lots of RAM when the 64-bit version comes out - 8-16GB worth? Any help is appreciated. Thank you.

P35-DS3R or P5K SE or P5K. Go with DDR2 800 RAM. Probably 3*2GB or more. Be careful with RAM natively higher than DDR2 800, most boards seems to have problems with RAM higher than DDR2 800.

( I know the P35-DS3R have problems with above DDR2 800, not sure on other boards)

Edit: PS I haven't looked at the new Sony Vagas, (still using 6.x) so is the new version Multithreaded?

Thanks for the info. So you're saying DDR2 1066 or higher can be unstable? Would there be any point in going to an X38 system? Or is that overkill for the processor?

Re: Sony Vegas
It's been multi-threaded since at least version 6 (maybe even earlier, but I'm not sure). And it scales very nicely on multiple cores - from the stats I've seen on the Sony Media Forum there's a linear 1 to 1 performance boost for each core added. The 64 bit version still in development is supposed to be the cat's meow.

There is no point on getting a X38/DDR2 1066. (Yes 1066 is quite unstable). As for the Q9450 it may be an over kill. BUT, the 12MB Cache would be quite useful. If you can live with a few seconds/minutes higher rendering time go with a Q9300 which is about $50 less. Thanks for the info on Vagas. . You need at least 2.5GB for editing vids on Vista. (4GB or more recommended). Another question: Is Vagas going to be XP x64 compatible?

Thanks, that's good news on using DDR2 800 (sort of), saves some money that I can put elsewhere . Don't know about XP 64 compatibility and Vegas. Some people have the current version of Vegas running fine on XP 64. Just have to wait and see when they release it.

Cool. What about the rest of the parts? (namely PSU, GPU)