Conserving DOS Conventional Memory
If the CD-ROM drive-support software is loaded in DOS conventional memory (below 640 KB RAM), there might be insufficient memory to run some DOS applications.
The CDSETUP program attempts to load the IDE CD-ROM drive device driver and
MSCDEX into upper memory, when possible, to avoid this problem.
For more information on techniques to conserve conventional memory, refer to the
following topics in the documentation that comes with the operating system:
DOS=UMB, DOS=HIGH,UMB (CONFIG.SYS entry)
This command enables the use of upper memory and loads DOS, MSCDEX, and
the IDE CD-ROM device driver in upper memory.
HIMEM.SYS (CONFIG.SYS entry)
This is a device driver that manages extended memory (RAM memory above 1 MB).
Windows automatically loads this device driver.
EMM386.EXE (CONFIG.SYS entry)
This is a device driver that allows the extended memory made available by
HIMEM.SYS to be used as expanded memory.
You might use the MSCDEX /E parameter with this device driver to move the cache that is allocated by MSCDEX
into this memory, thus freeing some conventional memory.
MEM /C /P (use from DOS prompt)
This is a useful DOS utility that displays the current memory allocation in the
computer to help you understand where device drivers and programs are located.
To display the MEM parameters available, at the DOS prompt, type mem /?
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