640K to 1M - some cite either
Also called "Real Memory"
Conventional Memory
Conventional memory refers to the memory reserved to run DOS programs in a computer system. DOS only uses the first 640 kb of memory in a PC.
Most DOS applications utilize conventional memory. Many DOS applications can not utilize extended or expanded memory without special software. When you load device drivers into upper memory, you leave more conventional memory free for other applications to use.
Conventional
False
Extended memory refers to memory on an x86 platform PC above 1 Megabyte of memory. In the Intel personal computer world, the original CPU was only able to directly address up to 640K of memory. This was called conventional memory. Above that, up to 1 megabytes, was called expanded memory. Accessing the expanded memory required additional instruction to allow for bank switching. You used special hardware to "rename" sections (banks) of the expanded memory to something in the conventional range so that it could be accessed as if it were conventional memory. Extended memory is memory greater than 1 megabyte for later intel compatible x86 processors that could support it. Extended memory was accessed using standardized API functions that allow moving data to and from the memory area and management it.
I think its Add DOS=HIGH to your CONFIG.SYS
To activate himem.sys which frees up more conventional memory and allows for DOS to be loaded into the HMA (high memory area) It manages memory as a device
Some microprocessors have cache memory; this is high speed memory and, if you're lucky and a program is small, it may entirely run in cache memory. All microprocessors have memory as registers - these aren't memory in the conventional sense, but are temporary locations to store values being worked on, addresses in memory and so on.
256mb
By memory, not very big at all.
Infinity