Minimum RAM for IBM PC 5150 / 5160 boot up

[fs5500]

(I've tested it on PCE IBM PC emulator.)


1) IBM PC 5150 with 16KB RAM (Rev.A 16-64KB Mother Board, BIOS : 04/24/81 or 10/19/81)

IBM Basic C1.00 launched. (No DOS or Disk Based Operating System can be boot up. 32KB of higher RAM is needed to boot up from Floppy Drive.)


2) IBM PC 5150 with 16KB RAM (Rev.B 64-256KB Mother Board, BIOS : 10/27/82)

IBM Basic C1.10 launched. (No DOS or Disk Based Operating System can be boot up. 32KB of higher RAM is needed to boot up from Floppy Drive.)
But the error code of 1055 201 must be shown due to rack of RAM amount. Becuase mother board type is 64-256KB, minimum RAM must be 64KB.


3) IBM PC 5160 with 16KB RAM (64-256KB Mother Board, BIOS : 11/08/82)

IBM Basic C1.10 launched. (No DOS or Disk Based Operating System can be boot up. 32KB of higher RAM is needed to boot up from Floppy Drive.)
But the error code of 04000 FF 201 must be shown due to rack of RAM amount. Becuase mother board type is 64-256KB, minimum RAM must be 64KB.


4) IBM PC 5160 with 64KB RAM (256-640KB Mother Board, BIOS : 01/10/86)

(DOS or Disk Based Operating System can be boot up..)
But the error code of 10000 FF 201 must be shown due to rack of RAM amount under 80KB.
This mother board type is 256-640KB.


5) IBM PC 5160 with 64KB RAM (256-640KB Mother Board, BIOS : 05/09/86)

(DOS or Disk Based Operating System can be boot up..)
No error code is shown on 64KB RAM.
This mother board type is 256-640KB.

 

[Scali]

Interesting.
Could you extend the test by actually booting into DOS?
I would think that only DOS 1.0 and perhaps 1.1 would actually boot under 32K. I believe DOS 2.x and later would need more than that, probably at least 64K.

 

[fs5500]

Interesting.
Could you extend the test by actually booting into DOS?
I would think that only DOS 1.0 and perhaps 1.1 would actually boot under 32K. I believe DOS 2.x and later would need more than that, probably at least 64K.

I've tested it with IBM DOS 1.00 ~ 5.02.

This is list of Minimum RAM for IBM PC DOS

Version 1.00 / RAM : 32KB
Version 1.10 / RAM : 32KB
Version 2.00 / RAM : 48KB
Version 2.10 / RAM : 48KB
Version 3.00 / RAM : 64KB
Version 3.10 / RAM : 64KB
Version 3.20 / RAM : 96KB
Version 3.30 / RAM : 96KB
Version 4.00 / RAM : 128KB
Version 4.01 / RAM : 128KB
Version 5.00 / RAM : 256KB
Version 5.00.1 / RAM : 256KB
Version 5.02 / RAM : 256KB