Changeing the stacks settings in config.sys file?

[stppetty]

I'm trying to overclock to 1000mhz with my 750mhz Athlon.I'm able to get it running very stable at 964mhz with 1.85v at 1/3 cache .When I try 978mhz or 997mhz I get a windows protection error change the stacks settings in your config.sys file.Is their say a limit setting in config.sys file that won't let me boot higher than that setting or is it just saying It won't run stable ????Please help?I have this 1000mhz bug in me!!I have great cooling ,no heat problems.Thanks Ken.