What hardware to buy?

Hi all

I have been trialling the CAELinux at home and have an opportunity to use it now and then at work. I have been given a budget of £xx (not too much or I won't get it), to upgrade or replace my desktop to support it more efficiently.

I'm OK with monitor and would probably just get a dell pc or something pre-built.

My first choices would be

Any basic GPU
A core2 Intel CPU
2gb of ddr2 ram
two hard disks (sata 2) one for xp one for linux
..not sure what else.

Can anyone advise me on what to avoid ie sata2 or intel or ??

Thanks in advance.
Si