EPSON Equity 4SX/25, 4DX/33, and 4DX2/50

Jumper Settings

J7 J5

,J13

J15

Adapter, CMOS, and PQFP Jumper Settings

Jumper

Jumper

 

number

setting

Function

J5”’

On

Supports CGA adapters

 

Off’

Supports monochrome, EGA, MCGA, and

 

 

VGA adapters

J6

l-2’

Enabtes the built-in VGA display adapter

 

2-3

Disables the built-in VGA display adapter so

 

 

you can use a disphy adapter on an option

 

 

card in the computer as the primary adapter

JT”*

On

Returns CMOS RAM to the factory settings

 

Off’

Retains SETUP program settings

J8

l-2’

Reserved

 

 

 

J18

2-3

Gate A20 reset (standard setting for windows) I

 

Keyboard reset

J23”

1-2

Enables the WFP SW25 processor

 

12-3

DisaMes the PQFP SX/25 processor

•Factory setting

**Factory setting depends on type of processor on system board • ** Two pin jumpers

Processor

Jumper

Settings

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Processor

type

 

 

JlO

 

J l l

 

J12

 

 

486SX (in OverDrive socket)

 

2-3

 

2-3

 

Off

 

 

487SX (in OverDrive socket)

 

l-2

II

1-2

II

2-3

 

1

or 486SX PQFP

I

I

 

 

 

 

 

486DX (in OverDrive socket)

1 1-2

1 1-2

1 1-2

1

You need to change the processor jumper settings if you install a new processor chip. The settings for J10, J11, and J12 must correspond to the type of chip installed.

If the computer’s microprocessor is a FQFP type, it is surface- mounted on the main system board. To add an OverDrive processor, install it in the empty OverDrive socket and disable the original microprocessor by setting jumper J23 to position 2-3. Also make sure JlO, J11, and J12 are set correctly.

Processor Speed Jumper Settirzgs

Processor type

J19

520

521

J22

SXI25, DX2150

O

f f

Off

On

Off

(25 MHz)

 

 

 

 

 

DXI33, DX2/66

O

n

Off

Off

Off

(33 MHz)

 

 

 

 

 

You need to change the processor speed jumper settings if you replace a 25 MHz processor with a 33 MHz processor.

Processor Chips

If you have the 4SX/25 or 4DX/33 system, you can install an Intel OverDrive processor on the main system board to effectively double the internal clock speed of the computer’s microprocessor. Alternatively, for the 4SX/25, you can install the 487SX/25 microprocessor with built-in math coprocessor.

OverDrive Processors

System

OverDrive processor

4SW25ODP486-25

4DXl33ODP486-33

SIMM lnstallation

The computer comes with 4MB of memory installed in a SIMM socket. To increase the amount of memory in the computer up to 32MB, you can install 36-bit, fast-page mode SIMMs that operate at an access speed of 70ns or faster, with a capacity of 1MB, 4MB, or 16MB.

The following table shows the possible SIMM configurations; do not install memory in any other configuration. Make sure that both SIMMs operate at the same speed.

SIMM Configurations

SiMM 0

 

SIMM 1

1 Total memory

 

 

4MB

 

 

 

14MB’

 

 

 

 

 

. . ..-

 

. . ..-

I

 

 

i AMR

i AMR

 

 

 

 

 

 

 

 

 

 

B

1 1MB

I5MB

 

 

 

B

 

4MB

 

5MB

 

 

 

B

 

4MB

 

8MB

 

 

16MB

 

 

 

4MB

20MB

 

 

 

 

 

 

 

 

 

4MiB

 

 

16MB

20MB

 

 

 

 

 

 

 

 

 

16L 1B

 

 

16MB

32MB

 

t

 

 

 

 

 

* Standard

memory

 

 

EPSON Equity-6

4/1/93