What's missing in your post in the POWER SUPPLY RATING. http://www.tomshardware.com/howto/20040122/ may see us fit something much larger and I can't tell if that is your issue or a software/driver issue. People often think that "it worked before" is a sign the power supply is proper. Think again. The electrolytic capacitors age and in months to a year, the power supply is some 20 or more percent less capable in many areas.
Unless you've fitted a monster supply, this can dog such a machine.
As to software and drivers, you get to boot Windows 2000 to SAFE MODE, remove all the video drivers, reboot and install just the VGA 256 color one and then update the motherboard drivers and top it off with the drivers from ATI that you know worked.
Best of luck,
Bob
Here are my system specs:
Win2k Server (updated)
Athlon 2500 (Barton), 1.8 GHz
Asus A7v333 MoBo
1 GB DDR 2700
2 80 GB Western Digital drives (mirrored)
Radeon 9100 (Sapphire Atlantis 9100) 4x AGP
Really been happy with the performance until a few days ago. "Startopia" crashed the video driver a couple times, and now when I reboot my resolution defaults back to 256 color and 640x480, but ATI 3D settings are retained. I've uninstalled everything ATI and even downloaded and installed the latest Catalyst driver ...same behavior. Any ideas?

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