Load drivers in high memory to free conventional memory
If having opened access to the Upper Memory Block (UMB), then one can load CDROM-drivers and other Terminate and Stay Resident (TSR) programs like DOSKEY.EXE into the Upper Memory Block (UMB) to increase the available conventional memory.
Edit AUTOEXEC.BAT and use LH/LOADHIGH:
LOADHIGH DOSKEY.EXE
Edit CONFIG.SYS and use DEVICEHIGH:
DEVICEHIGH=C:\CDROM\DRIVER.SYS
Note that if there is not enough free memory for the device to load in the UMB, then the device is loaded in the conventional memory. Therefore it might be a good idea to Check how much memory each TSR program uses and then order the loading of the TSR programs so the UMB is packed completely.
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