It's very difficult to compare the 2 chips, because it is impossible to have to two systems in which only the CPU is different using a G5 processer. G5's certainly have some advantages, however. Because the entire system is optimized for 64 bit processer speeds, they can use up to 8 gigs of ram at double the bandwidth. In applications such as photoshop, the G5 wins hands down over an FX-55. In the end, however, there are just too many variables to accurately benchmark the actual CPU's against eachother. However, in the few multiplatform benchmarks that aren't optimized for a paticular OS, the G5 is in the lead. However, the 'achilles heel' of all mac products is (their lack of) compatability with both hardware and software.

Which CPU wins out has everything to do with test conditions.
Apple couldn't get a dual CPU G5 to outperform a single CPU P4 machine even when they used an optimising compiler for the G5 and an non-optimising compiler for the P4 AND turned off hyperthreading on the P4 while finetuning the G5 for maximum performance...

Had they just used Photoshop and told it to perform some expensive manipulation it would likely have been faster but that wouldn't serve Apple's purpose of breaking out of the mold of being specialised graphics workstations

Some How i doubt that is true, as I remember reading stats and tons of test data, they are real work horses


It depends on what you really want to do, if its game and do regular windows like things, go with AMD64 and Windows XP

If you want to do alot more video, music, and graphics editing I would at least consider a dual g5 system.

But it comes down to personal prefrence.

Yeah, in compiling dual G5's would easily blow away a P4. No other system can handle 8 gigs of RAM. Anyone who does a lot of video/picture/music work/editing will use a mac. For example, on photoshop a single G5 outperforms a P4 3.4 ghz by 82% when they both have 2 gigs of ram. As the RAM increases, the 64 bit CPU will pull farther ahead. On the other hand, if your a serious gamer, an AMD chip is the way to go. It is faster than P4 (Max speed AND 'bang for your buck'). It all comes down to what you wll be using the system for. Many people complain that macs are overpriced, but I simply think you get what you pay for. Everything about the system is higher quality than your average Dell, from the cooling to the aesthetics to the raw power they offer.
PS: Dual 2.5ghz G5's would probably have over 3 times the performance when compiling than a P4 3.4ghz with hyper threading turned off.

so the G5 cpu is called G5?

Oh I thought it was made by intel or Amd, ok n/m then

... Um of course the G5 is called the G5, and it was designed by apple and IBM jointly (I think!) and is manufactured by IBM. It is only mac compatible.