I'm looking at getting a cheap, low power seconday computer to perform various tasks that I'd rather not do on my primary DAW.

The purposes of this machine would be:
1. Run spectrum analysis and various other monitoring tools using my old Delta 66 audio interface.
2. Allow me to play music from my network server.
3. Allow me to browse the internet.

I currently have a machine that is performing these duties, but it is old, slow, loud and generates and ungodly amount of heat. I do not need a fast machine, but getting one that has at least one free PCI slot (for the Delta 66) and is quiet and cool is a must.

THe AMD 1700+ CPU seems to put out a ton of heat.

SO should I buy a new cheap computer or just upgrade the old one with a new motherboard and CPU?