🚀 go-pugleaf

 > In article <844098206snz129.os2.7@artin.glassnet.com>,
 > Clive Humble <chumble@glassnet.com> wrote:
 >> 
 >> Hi chaps,
 >> 
 >> 
 >> I've just added a few more chips to my PC.
 >> 
...
 >> *********** System Information Tool -  ***********
 >> *********** Installed Memory Amounts ***********
 >> Memory Amounts by Operating System 
 >> Total amount memory detected by OS/2 : 97,900  Kilobytes 
 >> Total bytes of memory locked by OS/2 : 8,772   Kilobytes 
 >> Total amount of virtual memory free  : 651,456 Kilobytes 
 >> Page size of memory                  : 4,096   Bytes 
 >> Memory Amounts by Type 
 >> Base Memory                          : 640     Kilobytes 
 >> Total Usable                         : 65,152  Kilobytes 
 >> Extended Memory                      : 64,512  Kilobytes 
 >> System Board Memory                  : 65,152  Kilobytes 
 >> Cacheable Memory                     : 65,152  Kilobytes 
 >> *********** System Information Tool -  ***********
 >> 
 >> What's with the 'Total amount detected' and the last three
 >> stats..?
...
 >> What's with the 'Memory address about 16 Mb'

 >> Is something amiss ? Do I bring my box down to 64Mb and buy another
 >> kite with the 'lost' 32Mb..?

Here's the deal with PC memory:

  Memory above 1MB can't be addressed in real mode (but this is not an
  issue on an OS/2 system).

  Memory above 16MB can't be addressed by certain types of ISA cards 
  (e.g. most AT-bus SCSI controllers), since the AT bus has only 24 address
  lines. (This is not a problem for EISA or PCI cards.)

  Memory above 64MB often isn't cacheable without upgrading the cache chips
  on the motherboard (this fact is often buried deep in the documentation,
  if mentioned at all).

Those are the reasons why those limits keep cropping up. As to whether
your additional 32MB is being used, I would suspect from the figures above
that it isn't, presumably due to being non-cacheable.

-- 
Andrew Gierth (andrewg@microlise.co.uk)

"Ceterum censeo Microsoftam delendam esse" - Alain Knaff in nanam