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WD90C31 Local Bus Accelerator

From Higher Intellect Vintage Wiki

Jumper Settings[edit]

Category

Video

Video Types Supported

XVGA

Video Processor

WD90C31

Highest Resolution Supported

1280 X 1024

Data Bus Type

VESA local bus

Memory Type

DRAM

Maximum Onboard Memory

1024KB

CONNECTIONS

Purpose

Location

Purpose

Location

15-pin analog video port

J1

VGA feature connector

J2

DELAY CYCLE SELECTION

Delay

JP1

JP2

1 clock cycle (486/Pentium)

Pins 1 & 2 closed

Open

2 clock cycles (386)

Pins 2 & 3 closed

Closed

800 X 600 REFRESH RATE SELECTION

Refresh

SW1/1

SW1/2

56.5Hz

Off

Off

72.1Hz

On

Off

60.5Hz

Off

On

56.5Hz

On

On

1024 X 768 REFRESH RATE SELECTION

Refresh

Mode

SW1/3

SW1/4

86.7Hz

Interlaced

Off

Off

70.2Hz

Non-Interlaced

On

Off

60.2Hz

Non-Interlaced

Off

On

72.3Hz

Non-Interlaced

On

On

HORIZONTAL REFRESH RATE SELECTION

Refresh

SW1/5

31.5 KHz

Off

40 KHz

On