Robert.Berry@samba.acs.unc.edu (Robert Berry) (10/20/90)
I've been working with an old IBM PC (the original--2 floppies, monochrome monitor, 256K memory, etc.) at work and I want to make sure the DIP switches on the motherboard are set correctly. I have no hardware documentation, so can anyone tell me what the switches on each of the two switch blocks on the original PC motherboard designate? The only ones I'm sure of are 5 and 6 on switch block 1, which set the video adapter type. I have no idea what the second switch block is for at all. --
robin@uhunix1.uhcc.Hawaii.Edu (Robin Amano) (10/23/90)
In article <1370@beguine.UUCP> Robert.Berry@samba.acs.unc.edu (Robert Berry) writes: >I've been working with an old IBM PC (the original--2 floppies, monochrome >monitor, 256K memory, etc.) at work and I want to make sure the DIP >switches on the motherboard are set correctly. I have no hardware >documentation, so can anyone tell me what the switches on each of the >two switch blocks on the original PC motherboard designate? The only >ones I'm sure of are 5 and 6 on switch block 1, which set the video >adapter type. I have no idea what the second switch block is for at all. When upgrading to 640K look at the back of case should either have the letter A or B in a circle. If B you can upgrade, if A you need to have ROM replaced. SW1 ON OFF Number of 5 1/4" Drives 0 1,7,8 1 7,8 1 2 8 1,7 Math Coprocessor Installed 2 Math Coprocessor Not Installed 2 RAM Memory Installed on System Board 64K - 256K System Board 3,4 16K - 64K System Board 16K 3,4 32K 4 3 48K 3 4 64K 3,4 Monitor Adapter Installed None 5,6 Monochrome Monitor/Printer Adapter 5,6 Color Graphics Monitor Adapter 6 5 (40 X 25 Color) Color Graphics Monitor Adapter 5 6 (80 X 25 Color) SW2 ON OFF Note: Switches 6, 7, and 8 are always OFF. 16K - 64K System Board 16K - 64K (on Main Board) 1,2,3,4,5 96K 2,3,4,5 1 128K 1,3,4,5 2 160K 3,4,5 1,2 192K 1,2,4,5 3 224K 2,4,5 1,3 320K 1,2,3,5 4 352K 2,3,5 1,4 384K 1,3,5 2,4 416K 3,5 1,2,4 448K 1,2,5 3,4 480K 2,5 1,3,4 512K 1,5 2,3,4 544K 5 1,2,3,4 576K 1,2,3,4 5 608K 2,3,4 1,5 640K 1,3,4 2,5 64K - 256K System Board 64K 1,2,3,4,5 128K same as above Hope this helps. -- ---------------------------------------------------------------- Robin Amano | Internet: robin@uhunix.uhcc.hawaii.edu UHCC | 2565 The Mall | Honolulu, HI 96822