How Much Processer Do I Need? Options

[pigtails]

i am looking to buy a g4 powermac to run protools on. for the time being i will be using protools free, with a view to purchasing a m box later in the year. my tutor at college told me it's best to get a g4 with 1gig processor. however i have come across someone selling a g4 powermac and it's got 800mhz processor, 512ram 40gighard drive and is running os9 and os10.2. i am under the impression that i need os9 to run certain plug ins- if u know what i mean. i dont really understand about os. the bloke says it boots up in either os9 or os10. will this make a difference as to how it will run?
i'm really confused.......please help me.

[Synthetic]

here is a good example for you

I run PTLE 5.3 on a 350mhz G3 and up to 30 tracks of audio and sometimes midi with up to 4-8 plugs running. Sometimes its sluggish with all that going on but it handles it.

So... IMHO a g4800 will work well for you... but the only consideration is buying a an older computer puts in the middle of the cycle of upgrading.... meaning, as fast as computers get... newer software requirements require newer computers and you may feel compelled to upgrade you computer or CPU sooner than if you had bought one the faster models out. Makes sense? The idealogy is to always buy the fastest computer you can afford as it will last longer before the need to upgrade but sometimes saving some cash means more