why cant I run cas 3?

[treepop]

I want to get my fsb to 200+ and I would like to change my ram to say 8 4 4 3 but it wont even boot at 3 whats with that?.....same ram as in sig.....

[NookieN]

It might not be CAS that's causing the problem, but one of the others (probably RAS-CAS delay).

If you haven't already, try changing just one parameter at a time. That is, go 3-3-3-7, then 2.5-4-3-7, then 2.5-3-4-7... to see what does and doesn't work.

[Gnufsh]

http://www.lostcircuits.com/advice/bios2/6a.shtml

Perhaps your ram does not support cas 3, just 2 and 2.5