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.
Actually PooBaa I agree with what Stable stated. If he is manipulating huge files, there is a higher probablility of single bit errors. As for his point of high altitude he is also correct. There are less molecules to deflect incoming photons which can mess up a bit here and there. ECC would be much better in either case.
However for the registered verses regular form factors that will not matter. I don't really think that buffering the memory while using large files will matter much. If it was a whole bunch of little files and applications running at the same time I would say look into buffered memory. But if he is only using a few applications it is not needed.
Back to you...
<b>"If I melt dry ice in a bathtub, can I take a bath without getting wet?" - Steven Wright</b>
oh yes. ram brands like sambsung are also known to overclock extreemly well, up to PC3200 speeds in some cases.
infact many sticks of that expensive corsiar ram use sambsung chips that are handpicked to run at higher speeds.
just bear in mind there is considerable difference to running at 'plain' Cas2 compared with Turbo memtimings, cas2, everything set to absolutely hardest settings. etc
but even hardest settings are quite possible with a small ram voltage boost (+0.1 to +0.3)
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