IBM XT
Switch block 1:
Switch 1
off = Normal POST then Boot
ON = Continuous Power On Test (testing only!)
Switch 2
off = 8087 Math Chip installed
ON = 8087 NOT installed
Switch 3,4
ON,ON = One bank of memory
off,ON = Two banks
ON,off = Three banks
off,off = Four banks
Switch 5,6
off,off = MDA (or Hercules) Video
off,ON = 40 column CGA
ON,off = 80 column CGA
ON,ON = No video or special (EGA, VGA)
Switch 7,8
ON,ON = 1 floppy drive
off,ON = 2 flops
ON,off = 3 flops
off,off = 4 flops