Ah, time I started to look at this thread now
Frankly, a Mac or a PC running Windows XP are more or less equal to run decent music soft.
I am not talking Cool Edit Pro or Soundforge, but pro stuff like ProTools (mostly used by Mac-users, but also available for PC), Steinberg Cubase and Steinberg Nuendo.
I can only talk about the benefits of a PC since Apple refuses to lower their prices for me.
I bought a Dell Dimension 5000 for 1200 euro.
It has 1 gig memory, which is very important to work with these progs.
Also do not bother to buy a soundblaster soundcard.
If you mean serious business, buy a M-Audio or RME card instead. They cost almost half the price of your PC, but that is what you would spend on a Mac then
Don't waste half the money on something you have to throw away after a couple of days.
Also a big hard drive is recommended, but most important, a FAST drive! 7200 is the strict minimum. A 10000 rpm is even better.
Tweaking your windows XP is also highly recommended. I read the comment about Win98 consuming less resources than WinXP. That's true, but that's because WindowsXP runs a lot of s**t you do not need. Look at
http://www.musicxp.net/ for the quintessential stuff. Win Xp is a very stable OS, but it needs some guidance to push it in a certain direction
All these animated thingies and backdrop shadows are nice, but it is, after all, just eye-candy and slowing your PC down.
Also, use a separate partition to install Windows. Use another partition for your music soft. That way the access to your files is mucho faster.
Next up, try to use your music PC ONLY for music. Don't start to run games or PhotoShop on it just because it is such a big and fast machine. Even the biggest machines get clogged up after a while.
I even use my lappie for internet and the Big Machine is used for music only.
More tips if you need'em!
IZ.