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:
- Model 70 or Model 80 Processor Upgrade
- 132-Pin Socket Extender (only needed for 8570)
- Module-removal tool for extracting 80386 processor
- Option Diskette
- 70 486 or Model 80 486 Logo
- Co-processor compatibility plug (not included in FRU P/N 92F0436)
- Sheet of system labels
Default Switch settings:
| Switch Bank 1 |
SW-1 |
SW-2 |
SW-3 |
SW-4 |
SW-5 |
SW-6 |
SW-7 |
SW-8 |
| |
ON |
ON |
Off |
ON |
ON |
ON |
ON |
Off |
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
- Upgrade the Backup-Referencediskette (V-1.10 or higher) with the shipped
Option diskette. (use the COPY AN OPTION DISKETTE function)
- Power-OFF the computer
- Remove the Power-Cable
- Open/lift the Machine cover
- Remove Hard Disk(s) / Adapters (so you can freely operate with the
already installed processor)
- Locate the Processor on the System Board (Pin 1)
- Remove the Processor (80386)
- Remove the Co-processor ((80387) if any is installed)
- 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.
- Install the Co-processor compatibility plug into the Co-processor socket.
(be sure PIN-1 to PIN-1)
- Install the Processor Upgrade Board into the Processor socket
(be sure PIN-1 to Pin-1)
- Reinstall all previously removed Cable/Adapter
- Reconnect the Power cord
- Power-ON the system
- 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:
- Type A: to change to the root directory of drive A.
- Type slow to disable the cache
--- or ---
Type fast to enable the cache.
Some known Problems
- Cannot load Application Program
The application program might be speed sensitive. Refer to the application program manual for information on speed
(memory caching) requirements. See also in above Switch-table "Memory caching" above.
- Application Program Displays Damaged Data
Is an 80387 Coprocessor installed ? If yes then remove the Coprocessor and
install the Coprocessor compatibility plug.
- Cannot Load Windows 3.0 in Enhanced Mode
Check the CONFIG.SYS file for a line
device=C:\windows\smartdrv.sys 2048 1024
and change it to the following:
device=C:\windows\smartdrv.sys 2048 1024 \b-
This problem occurs only with the version of Smartdrive supplied with Windows V-3.0 and DOS V-5.0.
The Smartdrive supplied with Windows V-3.1 does not have this problem, nor does it use the same syntax
(enabling/disabling double buffering).
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