Thanks for all your help with my question the first time, but I forgot to mention a couple of things. The system is being built new, so the cpu is not replacing anything. The mobo (ECS K7VZA) does not have a jumper for the clock speed, and the best I can find in the Award Bios is "Frequency" where I can choose from things like "33Mhz + .05%".

Also, both the Mobo and the Athlon T-bird 1 Ghz chip have a 266 FSB, so that should not be my problem.

Plenty of power / fan / grease
266 megs ram

Any Ideas?

Load Optimized Defaults Option
This option opens a dialog box that lets you install optimized
defaults for all appropriate items in the Setup Utility. Press
and then to install the defaults. Press and then
to not install the defaults. The optimized defaults place
demands on the system that may be greater than the
performance level of the components, such as the CPU and the
memory. You can cause fatal errors or instability if you install the
optimized defaults when your hardware does not support them.
(If you only want to install setup defaults for a specific option,
select and display that option, and then press the key.)[try this for the cpu clk speed.]

their may be a newer bios version available
at
click here to go to http://www.ecs.com.tw/download/k7vza.htm

try posting here in the ecs forum at ocworkbench