Computer parts to upgrade for ableton (almost a new system)

[RickDawson]

new insides for about £300 (am flexible on cost)
I currently have in my tower an Athlon 64 3500+ 2.21GHz system.

I am looking to upgrade it, so I can run Ableton Live 8 (http://www.ableton.com) using vst instrument plug-ins without any CPU spikes.
and also so I can run visuals whilst broadcasting my DJ'ing online (http://www.tranceformers.net http://www.radio4by4.com/trance http://www.livegrooves.com)

I have an Antec TrueBlue 480w psu (ok to keep?)

case is fine - it is the original Silverstone Tek TJ04 (not the newer TJ04-E)

graphics is an x600 iirc? so will have to be upgraded?

soundcard is a creative x-fi (I still want to use it)

Harddrive has enough space to still keep it.

The motherboard, cpu, memory will be replaced.

I have a copy of windows to use for it.

existing external peripherals are fine.

roughly £300 GBP to spend.


suggestions please.

I will want to go and purchase from http://www.microdirect.co.uk and also http://www.aria.co.uk as I will visit them in person and purchase the parts direct from them.
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