Summary: I purchased the Radeon 9000 (non-Pro) and installed it in my 400Mhz Dell with Windows 2000 Professional. The card and software installed without a hitch. The manual talks about hooking up the card to a power supply. This is not applicable to the 9000 card (the manual was referring to the 9700 card).
Summary: Just added this card to my 3 year old Gateway Performance 800 (Pentium 3) which only had 8MB of onboard shared RAM. First I had to change the bios settings to support AGP graphics, which was simple. Installation of the card itself took only a few minutes.