I am building a new system and I am wondering if any of y'all have any preference when it comes to the Athlon 64 3200+ vs. the P4 3.2 chipset and why?

The box I am building will be for video editing, 3D, and compositing I want as much bang for the buck as I can get with a single processor. Tigerdirect has a sell on motherboards and cpus. Thanks for any help you can provide.

For Vegas, the Pentium has the edge in DSE's rendertest.veg (which is a bit contrived, but the only benchmark available for Vegas AFAIK). Hyperthreading gives about a 15% boost in Vegas, but it only really kicks in on short renders (which you don't care too much about) and when you run 2 instances of Vegas. The Pentium is faster at encoding MPEG2 with main concept's encoder.

I don't know about other NLEs. Some multithreaded ones will benefit from the Pentiums' hyperthreading.

For 3d apps, there are some benchmarks around like at xbitlabs.com and anandtech.com.

64bit isn't worth buying now because there are no useful applications of it for video editing. In 2 years time there might be some useful applications of 64bit computing and you are probably going to upgrade then.

The P3.2 is overpriced IMO but for some people it might actually be worth it. You can kinda of calculate it. A formula would be:
$ made =
time spent rendering X
hourly wage X (how much your time is worth)
% of time wasted rendering X (most people go to sleep or take a break while rendering, so not much time is wasted. You can also be thinking about your project while you are rendering. I'd assume 10%)
% of time you are spending compared to a slower processor (about 93.75% or higher)
The 3.2ghz is about 6.6% faster then the 3.0ghz if you assume performance increase is linear (which is kinda true with Vegas Video, but not all programs). 6.6% is a underwhelming performance increase though.

Something that isn't considered is the price of hitting a deadline. On a 15 hour render you would save ~1 hour.

Great summary , Glenn.

I'd like to add that even within a processor family, CPU speed increases don't necessarily translate to greater rendering speeds.
However, that won't stop Intel or AMD from selling them to you at a higher price. Since most rendering jobs don't fit on the CPU, the interaction with main memory is a major performance consideration. Overall, get the processor with the fastest main memory interface, or Front Side Bus (FSB).

I don't think the 64-bit Athlon is a great buy. People cite that one needs 64-bit applications for a performance increase, but don't overlook the larger on-chip caches. The nVidia chipsets offer an easy to use overclocking utility, so you may actually be able to get
an AthlonXP to run faster. As Glenn states, very few applications have been optimized for AMDs special instructions, so your best bang for the buck in video is probably the Pentium4.

So, Glenn, I am currently editing weddings with Vegas on my old Athlon 900mz. I am updating to a P4 3.2. You saying I'm going to see some increase in performance?

A higher FSB is interrelated to other changes in your system, but if comparing similar processors (Penitum "B"s that run at 4X133mhz FSB to "C"s that run at 4X200mhz FSB) then the extra FSB will mean that your RAM runs faster (200mhz instead of 133mhz). On my system (running dual channel RAM), the difference between 200mhz RAM (DDR400) and 133mhz RAM (DDR266) is about 2%. My testing methodology isn't exactly accurate since I bumped my RAM down using a memory divider, which slows things down.

If you are buying a new processor/motherboard/RAM, you should probably get the 800mhz FSB pentiums instead of the 533mhz ones and run dual channel PC3200 (DDR400) RAM. The RAM should be all the same model (same capacity and physical layout) and installed in pairs for optimal performance.

I'd like to add that even within a processor family, CPU speed increases don't necessarily translate to greater rendering speeds.
Overclocking my processor, it seems that performance gains are close to linear. I haven't fully tested that though, but basically all NLEs run this way. Faster CPU = faster rendering + more real-time.

I don't think the 64-bit Athlon is a great buy. People cite that one needs 64-bit applications for a performance increase, but don't overlook the larger on-chip caches.
Theoretically the cache might make a difference, but benchmarks generally show that the difference is not that much. One exception is Celerons VS Pentiums (Celerons suck).

The nVidia chipsets offer an easy to use overclocking utility, so you may actually be able to get
an AthlonXP to run faster. As Glenn states, very few applications have been optimized for AMDs special instructions[...]
Well actually it's that some applications are optimized for the SSE2+ instructions, which some AMDs don't even have and the XP ones aren't very good at (significantly slower). The AMD64 closes the gap though.

So, Glenn, I am currently editing weddings with Vegas on my old Athlon 900mz. I am updating to a P4 3.2. You saying I'm going to see some increase in performance?
Lol, of course! The 3.2ghz might be a waste of money though. The 2.8ghz and 3.0mhz ones make more sense. It depends how much rendering you do, how productive you are while rendering, and how important rush jobs are. It's hard for me to tell the difference between a 3.2ghz and a 3.0ghz. The difference is up to 6.6% and would only be noticeable on overnight renders, where you'd save 1 hour on a 15 hour render.