would a dual 1.25ghz render faster for editing than a single 1.6ghz G5?
 

my friend is currently looking to buy a computer and it seems that once you spec out the g4 that they have left on the website it is about the same price as the single g5. i know they g4 has room for two optical drives versus the g5 one. and that the g4 has four hard drive bays while the g5 has two. but speed wise would the dual g4 render faster than the sinle g5

My guess is the G5 will render faster. Several factors to consider, capability for much more ram and FCP 4 optimized for the G5 chip set.

The G5 will render faster. Even if initially, FCP 4 or other NLEs may run slow but once optimized for 64-bit (thanks Jeff), it will run very FAST. But thanks to Apple's introduction of Xcode, developers will be able to compile new lines of clean coding for the G5 in VERY short time. The pipelines in the new G5 are just very well designed, allowing much more bandwidth compared to the old G4 PowerMacs. Also, if you friend want to buy a PowerMac, consider this: the G4 PowerMacs Apple is selling right now is the older models that boot into OS 9 (which is a good thing for many) but does not have FW800 or Bluetooth. The top of the line dual G4 Apple is selling is more EXPENSIVE than the top of the line dual G5 PowerMac. $3,274.00 compared to $2999.

Hope that helps,

Phong

The top of the line G4 costs more because it is loaded with overpriced RAM. Buy Kingston or Crucial RAM from a 3rd party to save 50% or so (unless you want 1GB chips, which may not be available right now).

I'm not so sure 64-bit computing will help with Final Cut Pro. It allows for larger numbers, but right now DV is 8bit, uncompressed 10bit, and the most intense rendering 32-bit floating point. The processor is certainly something else, but without good benchmarks then you really don't know which is faster. It looks like the G5 will be faster though. soundtracklounge.com got a sneak peek at the G5 with some tests I believe.

The bit rate of your data files doesn't really matter. The G5 will execute more instructions per cycle. It will play back more audio channels simultaneously, video channels etc. Apples own tests have the G5 out performing G4's by a good distance.

The G5's can presently address up to 8gb of ram. They also include FireWire 800, have much faster front side busses and will run quieter. The first upgrade to FCP 4 will probably be a partial rewrite to better utilize the 64 bit architecture. Unless money was a real problem or you needed OS 9 compatibility, there's no reason to get a G4.

Did Apple publish their own tests anywhere? I would like to see em. NASA did publish some tests for the G5s but it was totally unrelated to video editing.
http://members.cox.net/craig.hunter/g5/

Look on Apple's site. they had some fairly extensive testing of the G5 against several PC's when it was first announced. I think now all they show is a bar graph of a few tests.

Those tests don't compare the G5 to the G4 (maybe because apple wants to sell those?). The Pentium 3 with hyperthreading tends to whoop the G4 though in other benchmarks- about 30%. However there are many ways to skew benchmarks so a direct comparison between a G5 and a G4 at Final Cut Pro would be useful.

The two single chip models started shipping yesterday, so you'll see some comparisons soon. Dual processor model promised to start shipping later this month.