Epson 4DX/33 - Manual (Page 6)

EPSON Endeavor 4SX/25, 4DX/33, and 4DX2/50
Jumper Settings
J7 J5
Adapter, CMOS, and PQFP jumper Settings
J13
J15
Jumper
number
J5***
J6
J7***
J6
Jumper
setting
On
Off*
1-2*
2-3
On
Off’
1-2*
Function
Supports CGA adapters
Supports monochrome, EGA, MCGA, and
VGA adapters
Enables the built-in VGA display adapter
Disables the built-in VGA display adapter so
you can use a display adapter on an option
card in the computer as the primary adapter
Returns CMOS RAM to the factory settings
Retains SETUP program settings
Reserved
J18 1-2*
2-3
J23** 1-2
2-3
* Factory setting
**
Gate A20 reset (standard setting for windows)
Keyboard reset
Enables the WFP SX/25 processor
Disables the PQFP SX/25 processor
Factory setting depends on type of processor on system board
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** Two pin jumpers
Processor Jumper Settings
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 J10, J11, and J12 are set correctly.
Processor Speed Jumper Settings
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
4SX/25 ODP486-25
40X/33 ODP486-33
SIMM Installation
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 Total memory
4MB 4MB *
4MB 4MB
4MB 1MB 5MB
1MB 4MB 5MB
4MB 4MB 8MB
16MB 16MB
16MB 16MB
16MB 1MB 17MB
1MB 16MB 17MB
16MB 4MB 20MB
4MB 16MB 20MB
16MB 16MB 32MB
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Standard memory
EPSON Endeavor-6 4/1/93