[comp.sys.ibm.pc] Memory above 640K, below 1Meg?

bose@iuvax.cs.indiana.edu (01/22/88)

I have a PS/2 Model 80 with 1Meg of memory.  Under Dos3.3 I am able to
allocate a diskcahe and a vdisk in the memory above 640K by using the 
/E (for extended memory) on those device drivers.  My understanding is
that this area is reserved!.  

Why is it that these drivers are allowing me to set up these devices in 
this area, and what are the possible problems that could happen?  

What happens when I add an extra 1Meg to my system?  If I allocate a diskcache
it would probably first allocate in the area above 640K and then eventually 
move past the 1Meg point.  This would still be allocating the cache in the reserved area and may still cause problems.