I want to thank everyone who replied with suggestions, opinions and personal experience with video cards. I finally decided on the Sapphire Radeon HD 2600PRO 256MB 128-bit GDDR2 PCI Express x16 card. Price, performance and reputation came together in the proper proportions. Installed the card and software and so far, excellent!
No more problems with artifacts. Civ IV and Red Alert Aftermath work without crashing the system. Dual DVI-I + HDTV outputs (only using the two DVI interfaces at the moment). And no underclocking necessary! Again, thanks to all who responded. Jim Maki [EMAIL PROTECTED]