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386 AT MARK II SYSTEM MOTHERBOARD
AMERICAN MEGATRENDS, INC.
386 AT MARK II SYSTEM MOTHERBOARD
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Processor
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80386
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Processor Speed
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16/20/25/33MHz
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Chip Set
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Unidentified
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Video Chip Set
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None
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Maximum Onboard Memory
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16MB (8MB on external memory card)
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Maximum Video Memory
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None
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Cache
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None
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BIOS
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AMI
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Dimensions
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355mm x 304mm
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I/O Options
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External memory card
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NPU Options
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80387/3167
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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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Turbo LED
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J1
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Power LED & keylock
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J8
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Reset switch
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J2
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External battery
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J9
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Speaker
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J7
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External memory card
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SL1
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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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Factory configured - do not alter
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J26
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Unidentified
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Factory configured - do not alter
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SW/1
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Off
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Monitor type select color
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SW/2
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On
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Monitor type select monochrome
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SW/2
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Off
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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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1MB
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(36) 41256
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None
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1MB
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None
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(4) 256K x 9
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2MB
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(36) 41256
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(4) 256K x 9
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4MB
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(36) 411000
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None
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4MB
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None
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(4) 1M x 9
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5MB
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(36) 41256
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(4) 1M x 9
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5MB
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(36) 411000
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(4) 256K x 9
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8MB
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(36) 411000
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(4) 1M x 9
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16MB
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None
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(4) 4M x 9
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Note: Board will accept 441000 chips but the configuration was not available.
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DRAM JUMPER CONFIGURATION
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Bank 0 chips
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Bank 1 chips
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J27
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Installed
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Not installed
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Pins 1 & 2, 3 & 4 closed
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Not installed
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Installed
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Pins 2 & 3, 4 & 5 closed
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41256
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256K/1M
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Pins 1 & 2, 3 & 4 closed
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411000
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256K/1M
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Pins 2 & 3, 4 & 5 closed
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441000
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Any chip type
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Pins 1 & 2, 3 & 4 closed
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Any chip type
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4M
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Pins 2 & 3, 4 & 5 closed
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DRAM CONFIGURATION
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Size
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Bank 2
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Bank 3
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8MB
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(18) 411000
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(18) 411000
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DRAM SWITCH CONFIGURATION
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Mark II memory
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BASE board memory
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SW/1
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SW/2
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SW/3
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640KB
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1 bank
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Off
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On
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On
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896KB
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2 banks
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On
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On
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On
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1664KB
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1 bank
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Off
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Off
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On
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1920KB
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2 banks
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On
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Off
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On
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3712KB
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1 bank
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Off
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On
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On
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3968KB
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2 banks
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On
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On
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On
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4736KB
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1 bank
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Off
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On
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Off
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4992KB
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2 banks
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On
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On
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Off
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7808KB
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1 bank
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Off
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Off
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On
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8064KB
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2 banks
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On
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Off
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On
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N/A*
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2 banks
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On
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Off
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Off
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Note: * = Memory configuration in the 14MB & 15MB region is enabled. For all other configurations, the region is disabled.
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