TANDY  3000  (250-4001)             Settings            Faxback Doc. # 1362

* Denotes user changeable options.

Caution: Some of these jumper options should NEVER be changed,
         DO NOT tell a customer to change a jumper unless you know
         the purpose of that jumper setting.

Discrete Version Main Logic Board#
----------------------------------

Monitor Type*
E2-E3     Selects monochrome video option (standard)
E3-E4     Selects color video option

Memory Size*
E13-E14   Removed selects 512K onboard memory (standard)
E13-E14   Installed selects 640K onboard memory

ROM Size
E5-E9     Selects 27128 type ROM  (standard)
E7-E11    Selects 27128 type ROM  (standard)
E6-E10    Selects 27256 type ROM  (do not use)
E8-E12    Selects 27256 type ROM  (do not use)

Gate-Array Main Logic Board#
------------------------------

Monitor Type*
E4-E5    Selects color video option
E5-E6    Selects monochrome video option (standard)

Memory Size*
E7-E8     E9-E10     RAM
------------------------
OFF       ON         512K
ON        OFF        640K
OFF       OFF        1MEG

ROM Size
E11-E15 & E13-E17     Selects 16K ROM (standard)
E12-E16 & E14-E18     Selects 32K ROM (do not use)

# The Gate-Array Main logic Board can be easily identified by the five
  large square Chips and Technologies chips.  The have "CHIPS" printed
  boldly on the top of each chip.


Color and Monochrome jumper options for the Tandy 3000 :

Discrete Version Main Logic Board
----------------------------------

Monitor Type
E2-E3     Selects monochrome video option (standard)
E3-E4     Selects color video option

Gate-Array Main Logic Board
------------------------------

Monitor Type
E4-E5    Selects color video option
E5-E6    Selects monochrome video option (standard)