Hello, I have a couple of IBM thinkcentre 8172 sff desktops that need new PSU. Have not been able to find an new replacement at a reasonable price. If anyone knows of one I would appreciate?Can I use a generic $15-20 PSU and leave it outside of the small case and just run the wires through the back where the old one was? Supprising how many of these computers were made and now replacement PSU's are available.