PS/2 8580 Processor Upgrade Options

Processor speed comparisons

Reply PowerBoard and TurboBoard Planar Upgrades
Kingston McMaster BusMaster Adapters
Kingston Processor Upgrades
IBM "Daughter" Processor Cards
IBM Planar Upgrades
Cyrix 486DRx2 16/32 and 20/40 and 25/50
Texas Instruments TX486DLC/E - 40GA


CAUTION: The use of some high speed processors requires a careful consideration of both voltage variations and socket differences intend to provide information about this later, unless I can find another site with a good description of these considerations. Also, many of these hardware options require matching software upgrades in order to obtain performance gains.

Processor speed comparisons

Norton
Index
LandMark Upgrade Description Planar /
CPU Base
11.0 386DX-16
17.5 24 386DX-20
26.7 39 386DX-25
48.1 114 Cx486DRx2 20/40 386DX-20
54.0 Kingston McMaster /Intel 486SX-25 386DX-20
63.4 146 Cx486DRx2 25/50 386DX-25
101 Kingston 486/Now / 486DX-33 386DX-xx
71.3 112 Kingston McMaster / Intel 486DX-33 386DX-xx
72.0 Reply PowerBoard / Intel DX-33 N/A
99.1 153 Kingston Lightning.486 / IBM 486DLC2-66 386DX-xx
108.0 168 Kingston McMaster /Intel 486DX2/50 386DX-xx
190.3 335 Reply PowerBoard /AMD 5x86/133 @ 100MHz N/A
196.1 364 Kingston McMaster / Intel DX4ODPR100 386DX-xx

Reply PowerBoard and TurboBoard Planar Upgrades

Reply Corporation is no longer in business. For a number of years, Reply manufactured replacement planar upgrades for a number of PS/2 models. The ones of interest here were made for the Model 60, 65, and 80 which all shared the same physical structure and also had many common parts. I am not familiar with the differences between the TurboBoard and the Power Board. Since I personally have one of the PowerBoard units and the documentation, the following comments will be restricted to the Power Board. Although these units were originally advertised as upgrade able to utilize the 133 MHz 486 products, the manual and my experience indicates that the supported processor limit is 100 MHz!

Features of the PowerBoard are:

  • 486DX2-50, 486DX2-66 and 486DX-100 processors
  • RAM support of 4MB to 64MB with "Industry Standard" 70ns parity SIMMs (4 SIMM slots)
  • SVGA support for up to 1024 x 768 with 256 colors, with 1MB standard, and expandable to 1024 x 768 with 64K colors with 2MB VRAM
  • Seven 32-bit MCA expansion slots (one with video extension), plus one 16-bit slot.
  • IDE (ATAPI) support for up to two drives, plus support for MCA controllers
Since this upgrade provides much faster video, as well as higher video resolutions, more 32-bit slots and direct support for 486 processors, it is a premium upgrade option.

Features of the TurboBoard are:

  • 486DX2-66 and 486DX-100 processors
  • RAM support of 4MB to 128MB with "Industry Standard" 70ns parity SIMMs (8 SIMM slots)
  • Seven 32-bit MCA expansion slots (one with video extension), plus one 16-bit slot.
  • IDE (ATAPI) support for up to two drives, plus support for MCA controllers (assumption of mine)
  • Socket 2 for processors

A photo of the TurboBoard is available on Tam Thi Pham's web-page.

Kingston McMaster BusMaster Adapters

There are several versions of this adapter available. The ones of interest have a 32-bit interface and provide a 168-pin 486 socket and can be used to upgrade either a 386 system or a 286 system. (There was an earlier version called an AOX McMaster which provided an upgrade adapter from a 286 system to a 386 system. I believe that the AOX company was bought by the Kingston Technology Corporation. This version is a 16-bit adapter and would not be appropriate for the 8580!.)

Like most Kingston adapters, different names exist for various configurations depending on the processor installed! For example, I have seen them described as MC33PD/xx, MC25PS/xx, MC50PD/xx and Kingston also lists MC33PS, MC66PD and MC133PD as discontinued models. Fortunately, the Kingston Technology Corporation still provides information on these adapters at their web site. Installation Guides for the MC25xx and MC33xx models are available at McMaster Guide #1 and for the MC133PD model at McMaster Guide #2. The ADF files and utility diskettes are available from McMaster software. Installation Guides for the MC25xx and MC33xx models are available at  McMaster Guide for MC25/33/50/66 and for the MC133PD model at McMaster Guide for MC133PD. Also download ADF files MICROADF.EXE and the utility diskette MCMR236.EXE.

There are jumpers J100 for designation of DX (1-2) or SX (2-3) processors and J801 for non-IBM SIMMs (1-2) or IBM SIMMs (2-3). For the more adventurous, the 33 MHz adapters have both 25 MHz oscillators (Y100) and 33 MHz oscillators (Y101), whereas the 25 MHz adapters lack the oscillator at Y101. Next to these oscillators is a hardwired jumper (J102) with a soldered link between (1-2) on the 33 MHz adapter and (2-3) on the 25 MHz adapter.

A possible unofficial upgrade may have been discovered by Jim Shorney who was feeling adventurous and took a 25 MHz adapter and installed a 32 MHz oscillator in Y101 and replaced the hardwired jumper with a jumper block and connected (1-2). The result was an adapter that worked with a base rate of 32 MHz and could potentially support one of the various 5x86-133 upgrade processors. Jim advises that he used an oscillator from one of the newer 8570 planars, as the oscillator physical size and pin configuration does not match the size and location of the more common larger DIP style oscillators. However, he has since reported that the upgrade has not been very reliable, but the cause has not been identified. I would appreciate hearing from anyone else who has experience with this or similar changes.

An extract from a subsequent Usenet posting to comp.sys.ibm.ps2.hardware by Jim Shorney follows:
"To add to the MCMaster story, I have finally found a combination that makes Punkzilla, the fastest P70 in the west, stable with the 25 MHz MCMaster overclocked to 32 MHz.  To recap, the machine would lock up over a period of several hours running Win3.11 and Logstat 5.1 as a test program.  This behaviour occurred with an Intel DX2-66 CPU and an AMD 5x86-133ADZ, and did not appear related to cooling.  The current combination has a Cyrix/IBM Blue Lightning 486-100 CPU with interposer, and over the past several days, has proven to be stable.  It has run 24+ hours without lockup, but must have the planar memory disabled in the MCMaster setup or it locks up almost immediately."

Important tips:

  1. The first SIMM must be installed in U900. A single SIMM in U901 (closest to thumb tab) will not be recognized! From personal experience, this can lead to frustration.
  2. The J801 jumper block must have jumpers between 1 & 2 when 16MB or 32MB SIMMS are used.
  3. Limit your choice of upgrade processors to 100MHz when using the MC33xx version. (The 133MHz processor will run OK at 100MHz on the 25MHz Adapters) If anyone has had any long-term success with any 133 MHz processor on the MC33xx adapter, please contact me with revision levels of your adapter.

Many people have asked about the empty white connector (upper right corner). This is identified as a Local-Bus Video Socket and there is no know module to use this slot. It is assumed that this was another feature that was announced, but never implemented. Anyone with information on this is asked to contact me.

Kingston Processor Upgrades

Kingston also produced several other interesting upgrades involving replacement of the processor with a faster processor on a small daughter-board which is inserted into the 386 processor socket. They consisted of:

Kingston 486/NOW! (Part Numbers 486/33PD3, 486/33PS3 and 486/25PS3)

These upgrades provide a 486 processor with clock speeds of either 25MHz or 33MHz. The PD models includes a math co-processor and the PS models do not. There are also different part numbers for the Model P70 which might not work correctly in the Model 80. If you are interested in more details, the  Kingston NOW! Installation Guide  is still available at the Kingston support site.

Lightning/486 (Part Number 486/BL66)

This upgrade consisted of the IBM Blue Lightning processor (486DLC processor running internally at a clock-doubled rate of 66MHz). If you are interested in details, the  Lightning/486 Installation Guide is still available at the Kingston support site.

IBM "Daughter" Processor Upgrade Cards

IBM sold several replacement processor card. These were similar to the Kingston upgrades mentioned earlier.

IBM Planar Upgrades

IBM sold a replacement planar, but it was an expensive upgrade and not many of these are likely to be located.
It is identified in the HMM as "Models 60, 65, and 80 486DX2 and 486DLC2 System Board Upgrade" and a diagram is available in PS/2 HMM (PDF), page 202.

Cyrix 486DRx2 16/32 and 20/40 and 25/50

Cyrix produced a family of 486 chips which provided a 486 processor with clock-doubled speed internally for each of the three different 8580 motherboards. They claim that it is necessary to match the correct speed. Software (driver) is required.

Texas Instruments TX486DLC/E - 40GA

Texas Instruments manufactured a direct replacement 486 processor with the 386-style 132-pin PGA socket configuration. Software (driver) is required in order to activate the internal cache and gain the performance advantage of using this chip. Since this chip runs at the same speed as the planar, the gain is limited.

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