If you are purchasing a system for Video Editing, I would recommend that you probably shouldn't even be looking at an Intel System based on DDR-RAM, but rather one based on RAMBUS (RDRAM) where you will get a significant performance increase! In this case, I would say motherboards utilizing the Intel 850E Chipset are your best bet when it comes to P4 processors from Intel.
If you want to use DDR, then I would suggest changing platforms from Intel to AMD, quite frankly because of the limited performance of a P4 coupled with anything except RDRAM. In this case (using an AMD CPU based system), you should look strictly at CAS2 DDR (Versus CAS2.5 or CAS3) for Maximum performance unless you are going with "Registered" RAM.
If you are at high-altitude and/or editing/converting files greater than 512MB, I would highly recommend a system that is based on ECC RAM rather than using a system that exploits the much more common "Unbuffered" RAM.
With ECC you are much less likely to have data corruptions or processing errors that could cause you to lose valuable processing time and/or potentially corrupt your data.
Registered RAM would be the best (what is used in servers for maximum stability and data integrity); however, you lose at least half a tick by using registered DDR-RAM so performance will be lower when compared to Unbuffered or ECC RAM solutions.
As a final thought, you should checkout some of the Mpeg 4 rip times here in Tom's Motherboard Reviews to see various platforms and judge for yourself which platfrom would best suit your needs.
Steph
Stable Technologies
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