IBM 486DX33 Processor Upgrade Card

IBM PS/2 486DX33 Processor Upgrade Card (for Models 8570 8580)
(Upgraded systems should have a P1 label placed on the front cover.)

      Type 8570  FRU P/N 92F0436         MKT P/N xxxxxxx
      Type 8580  FRU P/N 92F0437         MKT P/N xxxxxxx

The IBM PS/2 486DX33 Processor Upgrade for Models 70 and 80 is an i486 accelerator for 16 MHz and 20 MHz 80386-based computers.
(Type 8570 "short" and "long" board version)
(Type 8580 Model 041 071 111 121 311 321 081 and 161 - 16 MHZ or 20 MHz only)

You must use 8570/80 Reference Diskette Version 1.10 or later.

Important In some cases, with the Processor Upgrade installed, the diagnostic tests for some Micro Channel adapters might indicate that the adapter is failing when the adapter actually operates correctly. If you experience this problem, do the following: Set SW-1 on the Processor Upgrade to OFF (SW-1 OFF = cache disable for testing purposes !)

If you hear ONE-long and TWO-short beeps when the computer starts, then this is normal if there is an 8514/A adapter installed.

The Upgrade Option package contains: 

Default Switch settings:

Switch Bank 1 SW-1 SW-2 SW-3 SW-4 SW-5 SW-6 SW-7 SW-8

Switch function

 1 ON   (default)  Cache on
   OFF            Cache off
 2 ON   (default)  Cache HIMEM enabled
   OFF            Do not flush cache on INT 9
 3 ON             Cache enabled C000-D000
   OFF  (default)  Cache disabled C000-D000
 4 ON   (default)  Cache system BIOS enabled
   OFF            Cache system BIOS disabled
 5 ON   (default)  do not change
   OFF            Not applicable
 6 ON   (default)  XGA video adapter (slows processor speed)
   OFF            No XGA present
 7 ON   (default)  cache all extended memory
   OFF            Disable cache above 14MB
 8 ON             Delay write cycles
   OFF  (default)  fast write cycles

Installing the Processor Upgrade

  1.  Upgrade the Backup-Referencediskette (V-1.10 or higher) with the shipped  Option diskette. (use the COPY AN OPTION DISKETTE function)
  2.  Power-OFF the computer
  3.  Remove the Power-Cable
  4.  Open/lift the Machine cover
  5.  Remove Hard Disk(s) / Adapters (so you can freely operate with the  already installed processor)
  6.  Locate the Processor on the System Board (Pin 1)
  7.  Remove the Processor (80386)
  8.  Remove the Co-processor ((80387) if any is installed)
  9.  If the machine is a 8570 and the processor is nearby the power supply fan  then insert the 132-Pin socket extender (Pin-1 to Pin-1) into the 80386 socket.
  10.  Install the Co-processor compatibility plug into the Co-processor socket.  (be sure PIN-1 to PIN-1)
  11.  Install the Processor Upgrade Board into the Processor socket  (be sure PIN-1 to Pin-1)
  12.  Reinstall all previously removed Cable/Adapter
  13.  Reconnect the Power cord
  14.  Power-ON the system
  15.  Run Setup / Test

Utilities on the Upgrade Option Diskette

To control the cache speed under DOS (but not a DOS session under OS/2) without restarting the computer, insert the Option Diskette in drive A and at the prompt:

  1.  Type A: to change to the root directory of drive A.
  2.  Type slow to disable the cache
      --- or ---
     Type fast to enable the cache.

Some known Problems

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