🚀 go-pugleaf

joker@diku.dk (Morten Christian Holmgreen) writes:

>stanton@haas.berkeley.edu (Richard Stanton) writes:

>>After many attempts (involving swapping memory from one slot to another...)
>>I have upgraded my Ps/2 model 90 from 8 to 16 Mb. However, when I fire it up,
>>it only counts up to 16000k (rather than 16384), and the reference disk tells
>>me I have 16Mb installed, but only 15.6Mb usable.

>I don't think you can do anything about that. I have 36M in my 95, but
>it "only" counts to 36480K bytes, NOT 36864K. The systems uses the 
>remaining 384K.

This is pretty well documented by IBM, both in the advertising technical
summaries and the reference material for the PS/2 systems.  

In some systems some (or most) of the stolen memory is used to provide
shadowing of the ROM BIOS (similar to what some third-party memory 
managers do).  Depending on the particular PC model, that feature may
be an option controlled by the reference diskette.

Many boxes steal various amounts of main memory for use by the hardware,
so this isn't unique to the PS/2.  It is the reason why users of MS Windows
with exactly 2 MB of memory installed usually find their system defaulting 
to standard instead of enchanted mode: the boundary point is 2 MB, and
their system sees only 2 MB minus delta.

Joe Morris / MITRE