when should i upgrade?

ive had my pc for about 3yrs now and i feel that its time to get a new one.
my pc is a pentium 4 3.2ghz,1gb ram,x800 pro,some cheapppp 20 dollar motherboard, 80 gb hard drive, 250 watt psu, soundblaster audigy 2 zs sound card.
i would like to know if i should get a new pc altogether or just some new stuff, or if i should wait till next yr.
i can spend up to 4k (aussie dollars).
i got a neat 19 inch lg monitor and just bought myself some new logitech z5500 speakers. any suggestions would be greatly appreciated.

Now is not really the time to buy. Wait until September. Prices are to drop on CPUs, new super CPU at a much lower cost are coming out, and you could get an older type system cheap.

Yes, an full upgrade would be in order if you are a gamer. You could always go the part route and buy hard drives, graphics card, or soundcard. Get the latest for each and install them in the new system. Try to get SATA drives, PCI-E video, and a good sound card always makes the music clearer.

thanks for the reply, ill wait until around the end of the year to get something good that'll last me about 3-5yrs hopefully.

....when your current computer is no longer powerful enough to deal with the applications you wish to run. and not before otherwise you are just wasting money

Wrong answer. The right answer is, when your pay check comes in

only if you have more money than brain cells