Epson 4SX/25 - Manual (Page 6)

EPSON Equity 4SX/25, 4DX/33, and 4DX2/50
Jumper Settings
J7 J5
J15
If the computer’s microprocessor is a type, it is
mounted on the main system board. To add an
processor, install it in the empty socket and
disable the original microprocessor by setting jumper J23 to
position 2-3. Also make sure J11, and J12 are set correctly.
Processor Speed Jumper
Processor type J22
O f f Off On Off
(25 MHz)
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 or system, you can install an
Intel processor on the main system board to
effectively double the internal clock speed of the computer’s
microprocessor. Alternatively, for the you can install
the microprocessor with built-in math coprocessor.
Processors
Adapter, CMOS, and PQFP Jumper Settings
System processor
Jumper
number Jumper
setting
On
Off’
2-3
On
Off’
l-2’
Function
Supports CGA adapters
Supports monochrome, EGA, MCGA, and
VGA adapters
built-in VGA display adapter
Disables the built-in VGA display adapter so
you can use a disphy adapter on an option
card in the computer as
primary adapter
Returns CMOS RAM to the factory settings
Retains SETUP program settings
Reserved
Gate A20 reset (standard setting for windows) I
2-3 Keyboard reset
1-2 Enables the WFP SW25 processor
l
Factory setting
the PQFP processor
Factory setting depends on type of processor on system board
l
** Two pin jumpers
Processor Jumper Settings
Processor type
(in socket)
487SX (in socket)
or 486SX PQFP
2-3
l-2
J l l J12
2-3 Off
1-2 2-3
I
I I I
I I I
486DX (in socket) 1-2 1-2 1-2
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.
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
Total memory 0 1
4MB
i AMR i AMR I . . ..- . . ..-
B
B 4MB
B
4Mi
4MB
B 20MB
32MB
Standard memory
EPSON Equity-6 4/1/93