Path: utzoo!attcan!uunet!tektronix!orca!mstevens
From: mstevens@orca.TEK.COM (Mike Stevens)
Newsgroups: comp.sys.ibm.pc
Subject: Is AT mainboard RAM useful between 640K & 1MB?
Keywords: AT, RAM, 640K
Message-ID: <2663@orca.TEK.COM>
Date: 11 Nov 88 21:00:55 GMT
Organization: Tektronix Inc., Wilsonville, OR
Lines: 19

I have a generic Taiwanese 286 AT clone which has motherboard RAM
settings for 512K, 640K, and 1MB.  I'm using a DTK BIOS with MSDOS 3.21.
When I upgraded from 512K to 1MB, I also upgraded the system configuration
info to reflect the memory size upgrade (yes, I changed the HW switches
too).  The system now reports 1MB on powerup (640K base memory, 384K
expanded memory).

QUESTION:  What do I need to do to USE the extra 384K of memory?  I
tried to set up a ramdisk, but since it isn't extended memory (>1MB),
the ramdisk was placed in "low" (<640K) memory.  The DOS manuals aren't
any help, and I haven't found anything with tells me how/if I can access the
640K - 1M byte space as general purpose RAM.  I know that the memory map
of the "standard" AT reserves the space for monochrome, EGA, CGA,
extended partition gateway, etc.  But if the mainboard allows the extra
384K, there must be some use I can put it to.  Any ideas??

Thanks for any help ....

Mike Stevens