I have underclocked a AMD K6-II 400 as a P233mmx
with good results. It is generally only possible if the
CPU is in the same "family class", -- and other mother
boards (that were "slightly" newer) would have also included
that chip in the range of CPU's supported...
(It can't be past a "break point" type of barrier.)
How about a BIOS upgrade to support that chip?
PS: I never even saw a Cyrix chip, but since they run hot,
it would actually be good for one to underclock it,
(Assuming it meets the above "speed range" requirements.)
Make sure you can "at least" return it for credit ...
                 Rick
----- Original Message -----
From: "Steven Walley" <[log in to unmask]>
> I have a motherboard that will accept as its fastest CPU a Cyrix M II 300 Mhz.
> I have not been able to locate one at that speed, but have found several
> available at 333 Mhz.

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