> >According to my source, there is a little known limitation with current
> >Pentium II processors that allow them to recognize or address a limit of
> >64Megs of RAM. This despite the fact that many high-end Pentium IIs are
> >advertised as being expandable in the RAM department to much higher
> >amounts. Could this be a case where the Pentium II motherboards
> will accept
> >higher amounts of RAM, but somehow the excess over 64Megs is not
> recognized
> >by the CPU?
>
> I don't buy this at all.
>
> What I do know, is that with 512K of L2 cache, only the first 64M of RAM
> will be cached.
> This has nothing to do with the CPU itself.  Motherboards with 1024K L2
> Cache have been
> coming on the market for at least 6 months any they will definately be the
> standard soon,
> since a lot of people are putting more than 64M in their system.
>
> So, in summary, it's the L2 cache size that limits the amount of RAM that
> can be cached.
> Too little cache size, and your system will take a definate
> perfomance hit.

        Almost right, cache amount does determine amount of memory it can cache,
but there is one thing you are missing, there is also a tag SRAM involved,
and it is the final determiner of
the amount of memory cachable. Now I don't know the numbers, but remember
the HX chipset? Most
motherboards with the HX chipset had 512K cache, capable of caching 64 megs,
but by adding a send tag SRAM chip the chipset could cache up to 512 megs,
so there are three determiners of
cachable memory, the chipset (or in the case of the Pentium II the processor
as well), the amount of cache, and the amount and type of tag SRAM. TTYL