I know I'm cheap - any options

I currently have an old computer that is running windows 98. I know, I know, step into the 21st century. But the fact is it's not doing me any good sitting in the corner. Would like to hook this up to my CNC and run Mach 3 on it. That will be the only thing running on it. Will it work? are there any options to make it work. Or do I just need to suck it up and upgrade?

Mach3 doesn't work on Windows98. It needs at least Windows 2000. And should be 1Ghz or faster.

If you have a copy of XP, or Win2K, you can get one of these, which is what I use. They're so cheap I have a spare. You need the correct Dell power supply for it, though. They run about $10.

Dell Optiplex GX150 2H240 Motherboard w/ 1Ghz 384MB | eBay