I bought an Ultra-X P.H.D. board after a trade show and I've been very happy with it. I got it packaged with their Quick Tech diagnostic software and some various plugs and control BIOS chips and they've helped out on a number of very dead systems. The board can find bad RAM (providing there is a working memory controller) and any number of other problems. I picked up the whole kit for under $1000 (show pricing) and I'd say I've got my money's worth out of it. My only regret is that I got the ISA version because at the time I was pretty much guaranteed to have ISA in any machine I was working on, but now with the legacy free machines, I kinda wish I'd gone with the PCI version. You can find them at http://www.uxd.com.