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From: ballard@cheddar.ucs.ubc.ca (Alan Ballard)
Subject: Re: Why only 3968K OK ?  4096K installed
Message-ID: <1991Apr5.171358.24842@unixg.ubc.ca>
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Organization: Computing Services, University of British Columbia
References: <1991Apr5.062809.1964@brolga.cc.uq.oz.au>
Date: Fri, 5 Apr 1991 17:13:58 GMT

In article <1991Apr5.062809.1964@brolga.cc.uq.oz.au> exnirad@brolga.cc.uq.oz.au (Nirad Sharma) writes:
>  My real question,  however,  is why does my machine with 4M of memory
>on the system board  (forget the before-mentioned memory card - its in a
>workshop somewhere :( )  boot up with only 3968K OK ?  Diagnostics etc
>says that 4096K is installed on the system board.
The model 80, and various other models, steal 128K of RAM to "shadow" the  
ROM -- at startup the BIOS copies the slow speed ROM to higher-speed RAM
and configures memory so all BIOS etc. references go to this RAM.  
Alan Ballard                   | Internet: ballard@ucs.ubc.ca
University Computing Services  |   Bitnet: USERAB1@UBCMTSG
University of British Columbia |    Phone: 604-822-3074
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