The AS1200 can support 4gigs of PC66 ECC SDRAM registered 
unbuffered.  The maximum size of each module being 
256mb (256mb * 16 slots = 4096mb).

I was told that PC100 ECC SDRAM registered unbuffered 
will work as well.  Infact, faster bus speed RAM will
work as long as it will meet the other requirements.  

I'm wondering if others are doing this?  When you look
at the prices of RAM today where the only difference
between the module is PC66 vs PC100 (other than the
price being double for the PC66!) you'd have to ask
this question too.

Thanks!