Minimum Old PC Requirements for LinuxCNC?

So, there's scads of old computers around, some with parallel ports, some without, so I'd prefer to get one of those for free and reuse it rather than having it be scrapped.
What's the minimum configuration that would be considered reasonable for running a 3+ axis CNC lathe or mill via parallel port with LinuxCNC?
Source for reasonable parallel port cards?
If parallel ports are a waste of time, please recommend some low cost 4+ axis motion controllers that would work with either LinuxCNC or Mach 3

I'd like to be able to get 300+ IPM rapids and have a C axis

BigJohnT wrote:

Is this a stepper machine? Very old PC's might need to run an older version of LinuxCNC. Get the DVD and boot then run the latency test.

JT

It’s for a machine that doesn’t exist yet except in my head. I would want to run the spindle as a C axis and each of the axes with step & direction probably. I don’t have any motion controllers, thus I am asking about parallel port control.
If there are reasonably priced 4+ axis motion controllers that would work, I am all ears.

BigJohnT wrote:

A stepper driven C axis?

The Mesa 7i96 is a very cost effective stepper card.

JT

Well, I’m thinking 3+ horsepower digital AC/brushless servo for the C/spindle

BigJohnT wrote:

A stepper driven C axis?

The Mesa 7i96 is a very cost effective stepper card.

JT

Thanks!
That is quite reasonable!
Doesn’t look like Mach supports it, but that’s not a necessity.

Any MPG recommendations?

Thanks!