New PC, what bits?

[Antinoise]

What is an UAD-1 card.

Universal Audio... Runs efx on the PCI card
http://www.uaudio.com/products/digital/UAD-1/index.html...
killer compressors

and should i really go 4 an internall? i could go live with an external but
will it be worth cutting back just for the sake of an external card.

If your going to go live then you are looking at a laptop rather than a
desktop. Walk before you can swim.... get a killer studio computer
(desktop) with a great soundcard (don't comparmize on external
firewire)... worry about live later.

and is 1536 mb ram enough?

thats overkill if anything