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4825 SX
TANDY/RADIO SHACK
4825 SX
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Processor
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80486SX/80487SX/80486DX/80486DX2
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Processor Speed
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25/33/50(internal)/66(internal)MHz
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Chip Set
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Unidentified
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Video Chip Set
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Unidentified
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Maximum Onboard Memory
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32MB
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Maximum Video Memory
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1MB
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Cache
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None
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BIOS
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Unidentified
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Dimensions
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394mm x 381mm
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I/O Options
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Floppy drive interface, IDE interface, parallel port, PS/2 mouse port, serial ports (2), VGA feature connector, VGA port, riser slot
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NPU Options
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None
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CONNECTIONS
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Purpose
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Location
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Purpose
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Location
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VGA port
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CN1
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IDE interface
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CN8
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PS/2 mouse port
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CN2
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External battery
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J1
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Parallel port
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CN3
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Speaker
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J2
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Serial port 2
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CN4
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Reset switch
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J3
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Serial port 1
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CN5
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Power LED
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J4
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VGA feature connector
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CN6
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Riser slot
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SL1
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Floppy drive interface
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CN7
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USER CONFIGURABLE SETTINGS
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Function
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Label
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Position
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»
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CMOS memory normal operation
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JP1
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Open
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CMOS memory clear
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JP1
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Closed
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»
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Monitor frequency select 31KHz
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SW1/5
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Off
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Monitor frequency select 40KHz
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SW1/5
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On
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»
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Monitor type select color
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SW2/3
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Off
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Monitor type select monochrome
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SW2/3
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On
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DRAM CONFIGURATION
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Size
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Bank 0
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Bank 1
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4MB
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(4) 1M x 9
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None
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5MB
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(4) 1M x 9
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(4) 256K x 9
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8MB
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(4) 1M x 9
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(4) 1M x 9
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16MB
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(4) 4M x 9
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None
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20MB
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(4) 1M x 9
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(4) 4M x 9
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32MB
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(4) 4M x 9
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(4) 4M x 9
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VIDEO MEMORY CONFIGURATION
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Size
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Bank 0
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Bank 1
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512KB
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512KB
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None
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1MB
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512KB
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512KB
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Note: The location of banks 0 & 1 are unidentified. The size of the video memory chips are unidentified.
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VIDEO MEMORY SWITCH CONFIGURATION
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Size
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SW1/6
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512KB
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On
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1MB
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Off
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CPU TYPE SELECTION
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Type
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SW2/1
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SW2/2
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80486SX
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Off
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Off
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80487SX
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On
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Off
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80486DX
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Off
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Off
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80486DX2
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Off
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Off
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VIDEO RESOLUTION SELECTION (800 X 600)
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Frequency
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SW1/1
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SW1/2
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| »
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56Hz
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Off
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Off
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60Hz
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Off
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On
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72Hz
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On
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Off
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56Hz
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On
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On
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VIDEO RESOLUTION SELECTION (1024 X 768)
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Frequency
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SW1/3
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SW1/4
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| »
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Interlaced
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Off
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Off
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60HZ non-interlaced
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Off
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On
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70HZ non-interlaced
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On
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Off
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Interlaced
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On
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On
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ON BOARD VIDEO SELECTION
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Setting
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SW1/7
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SW1/8
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| »
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Enabled
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On
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Off
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Disabled
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Off
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On
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