I have a renderfarm with two Mac and two Windows boxes, one with 256MB Ram/Pentium III (and Windows 2000 on it). Works. Of course the 256MB machine is not really rendering the majority but it renders its part without moaning. Sometimes even more tiles than the cow on the host Mac, depending what is happening on that host at that time. So yes, my experience is - all helps. Btw, i even run Infinite on the old little Windows box and use this as host computer for rendering.

One day your ship comes in - but you're at the airport.