386 CPU Upgrade 

Draft # 1.  2002.10.19
Draft # 2.  2002.10.27
 REV to 486

   IBM486SLC2 25/50

   TopLine ?

 486 Now

 Lightning 486
 MCMaster 486

 Improve it technology
 Make it 486   TI486SLC50


  IBM486SLC & Blue Lightning
  Interposer for Cyrix ( Evergreen ) 
  Cx486SRX2 25/50M P
  Cyrix CPU info     Tim O'Connor's page

  286 Processor Upgrades by Kingston
  ETPARTS.txt ( Evergreen Upgrades)

   I started MCA with 486 class machine and I'm not so familiar with 386 class computers and upgrade parts for those systems. Most of the products in my hands were collected at various Junk parts shops.  Some were alive and the others were dead maybe, not sure.

Cache enabling utilities are mandatory to use with these clock-multipling CPUs. 

Evergreen Technologies 
Evergreen made various kind of processor upgrading parts for 286 to 486 class systems. IBM486SLC and BL processors were mainly used for their upgrading products. For detailed parts list, please check Evergreen's ETPARTS.txt.

REV to 486    Please click here for associated utility ( requires a 720KB floppy )
386SX3+   Evergreen Parts # 300, # 279     Editor's recommendation.
IBM486 3x capable processors were used for these models. # 300 was for 20/60 or 25/75 upgrade and  # 279 
was for 16/48 upgrade.  In old Japanese catalog,  parts # 298  was listed for 16/24 to 25/75 systems. 
ETPARTS says the chips used for these models are "Blue Lightning 25/75" ( or 20/60 ). 

I'm wondering if  CPUs used for these Evergreen upgrades were really a "IBM486SLC3" processor or not.
Outlines for IBM 486SLC3 Processor upgrade in Louis's page seems that a CPU used for the upgrade card is same size with intel 386SX ( U4/SLC3 is smaller than U2/387SX ).  And also it is almost same with a CPU outlined in IBM486SLC2 Upgrade page.  While the chip used in Evergreens 3x speed upgrade in my hand is bigger than those used in above mentioned upgrade by IBM. The chip is just same size with IBM486BL3 used for their Processor Upgrade for 386DX systems. It seems to me that a real 32-bit Blue Lightning ( BL3 ) was used  for 386SX upgrading.   IBM486SLC2 is always refereed as "SLC2"  but not as "Blue Lightning ( at least  in old PC magazines in Japan ) .    Would like to see an exact "IBM486SLC3" used on "IBM 486SLC3 Processor Upgrade Kit or in model 57SLC3.

The model in pictures below is rated 20/60MHz but it is capable to run in 75MHz.  Don't know exact part  number  because  I got it free as "Junk" without packaging box.  Most possibly it is  # 300.    It run fine on 5530-U ( intel  386SX system ).  Then I tried to load it on 8557 Ultimedia and, in order to put it on IBM386SLC2 on the planar,  I grooved one corner of CPU holder.  Unfortunately 8557 didn't work  with the upgrade.  I didn't check further to clarify the reason why it didn't boot. 

Easy to use. Just snap it on atop of existing 386SX CPU. 


IBM486SLC2 25/50   EverGreen Parts number unknown 
Same as above. IBM486SLC2  is apparently different from BL2 or 3 above. SLC2 is smaller than BL  and  is just same size with Intel 386SX.

IBM486SCL25/25 was not available as a CPU "unit". Some of PC upgrade shop soldered off  IBM486SLC2s from PCB and then used those chips for their Laptop upgrade program.  One in my hand is a such PCB. 
You can see there are two set of solder pads ,for bigger cpu and smaller cpu. It's difficult to confirm through  photo but actually the inner solder pads were used ( CPU was once there. ).

TI486SLC2  EverGreen Parts # 289  ( but a package in my hand says # 288. Not so sure which is correct ) 
Tested it in my 5530-Uxx with intel 386SX, but it didn't work.  Don't know if this unit was defective or the kit itself is incompatible with 5530-U( i386SX ).  5530-U didn't boot at all. 

Important note:
  This  upgrade cpu is not compatible for systems which has a 386SX in step A and step B.
  Test your system using SXCHK.EXE if it yours is compatible with this upgrade. 
  SXCHK.EXE is contained in REV to 486 cache utility diskette.

    TI486SLC2 has 8KB L1 cache and it should be faster than Cyrix 486SLC with 1KB L1 cache.

386DX2+    Evergreen Parts # 271 and #272
TI486SXLC/2 series were used for these models. 
TI486SXLC/2 which was refereed as "TI Potomac" is clock-doubling CPU with 8KB L1 cache.

  When I pull off the CPU from the associated socket to take pictures,  A14 pin was torn off !   Oh, my... 
  Can I solder the pin ??? 

386DX3+ Editor's recommendation
IBM Blue LIghtning 3x processor ( BL3) was used for this model. Depending on system board clock, there were two versions available.
1.  IBM486BL3 20/60 EverGreen Parts # 261  ( not listed in ETPARTS.txt ) 
2.  IBM486BL3 25/75 EverGreen Parts # 263

If you don't consider clock rodding of Kingston Lightning 486 or 486Now,  REV to 486 386DX3+  is the fastest upgrade part to boost your 8570 or 8580.  There is a socket for co-processor but I have not ever seen co-pro for BL2/BL3 which fit to the socket on the PCB. Even without co-pro,  Evergreen's BL3 upgrades are really powerful.   A weak point of Evergreen's upgrades using  BL3 for 386 PGA socket is it's pin connection between PCB and  PGA socket.  Pins are soldered on solder pads on the surface of the PCB without holes. Thus excessive usage pushing it onto the PGA socket and removing it off from the socket may break the pin soldering like a picture below ( leftmost ) . 


 Click image to enlarge. You can see
 pins are not go through PCB, they
 are soldered on the PCB.

   Question: What is an IBM 486BL2 or 486BL3 (Blue Lightning) processor?
   Answer:   It is an IBM-developed derivative of the Intel 486SX chip that comes in two "flavors": 
                   the clock-doubling 486BL2 and clock-tripling 486BL3. 

TopLine  ?
I do not know if this is a CPU upgrade or not but it seems it is for upgrading 386SX.   At least my 5530-U didn't work with it. 
  Markings on the chip are;

Kingston's approach for 386 upgrading was a bit different from Evergreen. Their products have own clock gene- rator on the cards. Both 486 Now and Lightning 486 use own CPU external clock isolated from system clock of the planar.   Kingston still offers drivers and manuals at their web site. 

486 Now   see Louis's page for outline and detailed information. 

     Mine is from "garbage box" and without connection pins for PGA socket. I have both 20MHz and 33MHz 
     versions but both of them have not pin extender. 
     Would like to check if it can take 5x86ers. 

     486NOW.EXE   PS/2 486/Now! disk w/drivers. ( 240KB )
     COP487.SYS     Divide by zero error fix for 486/NOW! .( 1KB )


Lightning 486
Kingston's Lightning 486 may be considered as a counter product against Evergreens "REV to 486".
This unit has OSC on the card and CPU base clock is supplied from it's own clock generator but not from planar.   Card has 66MHz OSC and an IBM 486BL2-66 on the card run in 66MHz clock-doubled speed in any systems  regardless to main planar base clock such as 16MHz,  20MHz and 25MHz.
A surprising information was reported to the MCA Forum that the reporter used his Lighting 486  with 90MHz OSC installed and his lightning 486 actually run in 90MHz inner speed. 

For detailed information please click here ( Louis's page mirrored by William Walsh ).  The  page explaining about IBM 486DLC2 Upgrade but it is Kingston equivalent.

    486BL66.EXE     Lightning/486 (486BL/66) Diskette v1.0. 22KB
    LIGHT486.EXE    Lightning/486 Drive v1.2b.  151KB

    I don't have this one !

MCMaster 486
MCmaster was originally developed and sold by AOX . Kingston bought the company and whole products.
My MCmaster shows AOX logo when it get powered .  According to Louis's page there were several version of MCMaster.  For detailed information and outlines, please visit Louis's page

     MCMR236.EXE    MCMaster Utility Diskette v2.36  ( 218KB )
     MCMR235.EXE    MCMaster Utility Diskette v2.35  ( 266KB )
     MC2351.EXE       MCMaster Utility Diskette v2.35I  ( 57KB )

     picture is not ready

Brief tips for MCMaster
     1.  Do not use 2MB SIMMs.  it's not usable on MCMaster.
     2.  You can install two of  32MB SIMM  for 32bit system. ( I myself confirmed 16MB x2 on it. I didn't have
          32MB SIMMs back then ).
     3.  You can use 5x86 CPUs like Cyrix 5x86 or AMD 5x86-133 using voltage interposer but you will loose 
          a neighboring BUS slot.  For 8580 25MHz system, MCMaster and 5x86 CPU is recommended.

Improve it technologies
Not  sure about this company. I happened to get their product "Make it 486"  NIB .

Make it 486

When I bought my first 5570-V ( 8580-Axx analogous ) from a individual trader, the seller sold me some of  386 upgrade CPUs very cheap ( almost free ).  "Make it 486" was included in the volume.  Unfortunately now I don't have it. I gave it to a friend of mine.
Pictures below is scanned image of it's packaging box. As far as I remember outlook of  the kit (CPU) is different from a picture of the package.
In order to activate L1 cache, a special cache utility is required.  The driver was supplied in 5.25" floppy so I had to buy an external 5.25" floppy drive to read the driver.  I tested it on my 5541-T ( 386DX-20 system ). It was faster than Cyrix upgrades but slower than Evergreen's  REV to 486 386DX3+ in clock-doubled 50MHz operation.

  Pic #1  Front of the package
  Pic #2  Back of the package
  Pic #3  Important note  ( it says a CPU was different version from the pictures in the installation manual.)

  Make it 486 utility  ( DXP format. requires 720KB floppy )

    Brief note from "Setup Programs" guide sheet in the diskette envelope.
    " The Make-it 486 modules start up with the on-board cache not activate. This is a feature of the
      processor chip. The cache is required for high-speed operation of your new 486. Activation of the
      cache is accomplished by running a program each time your computer is powered up. A program
      to activate the cache ( CACHE486.EXE ) and a set-up program is on this diskette "


IBM 486SLC2/SLC3 and Blue Lightning     IBM has some Information about their products at their web sit.
Product Packaging Based ON 486 Instruction L1 Cache External BUS Rated   Vcc
386SLC QFP i386SX  8KB 16-bit 20-25   5V
386SLC2 QFP i386SX  8KB 16-bit 40-50, 2x   5V
486SLC QFP i386SX Supported 16KB 16-bit 25   3.6V
486SLC2 QFP i386SX Supported 16KB 16-bit 50, 2x   3.6V
486SLC3 QFP i386SX Supported 16KB 16-bit 75, 3x   3.6V
or 486BL2
QFP i486SX Supported 16KB 32-bit 66, 2x   3.3V 
486DLC2 PGA i486SX  Supported 16KB 32-bit 66, 2x   5V
486BL3  QFP i486SX Supported 16KB 32-bit 75, 3x   3.3V 
All of above listed CPU does not have Floating Point Unit( Math-CoPro ).
intel 486SX/DX has 8KB L1 cache.

Are you lucky?
Some laptops such as TP700/700C has an IBM486SLC25.  If you are lucky  your system may run in 50MHz inner speed using utility which enables clock-doubling circuit in the cpu (  if yours is actually a 486SLC2-50 
even though the system is rated at  25MHz ).  Few systems rated 25MHz have actually an IBM486SLC2-50.
For example, later model of TP550BJ ( with built-in Canon bubble-jet printer,  sold only inside Japan ) was 
announced that it had an "IBM486SLC" but  few of this model actually run at  50MHz when appropriate cache enabler is used. 

Interposer for Cyrix  made by Evergreen
     No information for this unit.  Maybe Cx486DLC25GP shown below is associated with this kit. 
     This one is not listed in ETPARTS text too.   Cache enabler maybe required for this upgrade kit.
Cx486DLC Specs
  132 pin PGA 
  1KB L1 cache
  Input Voltage :5V
  Pi compatible with i386DX

  TX486DLC is an equivalent.

Cx486SRX2 25/50M P
        Snap on kit upgrading 386SX system.   Don't know if it can be used in PS/2 or PS/55.
        This kit is compatible for i386SX in step C and later (  step D and combo step ) .
 Cx486SRX2 Spec
  Packaging: 100pin QFP
  External BUS: 16 bit
  1KB L1 Cache
  I/O 5V
  Pin compatible with i386SX
  Base clock: 16/20/25.   Runs at 32/40/50 


286 Processor Upgrades by Kingston.  ( May be a variation of 386SX Now )

Err.. honestly speaking, I'm not so sure if this is for 286 systems or for  386SX systems. If this one is for 386SX, it should be installed to 387SX PLCC socket like IBM 486SLC2 upgrade for 855x.  But the CPU is Cx486SLC-25, then it may be for 286systems, I think... 
I can't check the card if it is dead or alive, also if it is compatible with PS/2 or not.  I don't have 286 system this moment.  I just got the card in a grab together with some of above mentioned Upgrades.
     Cx486SLC  ( SLC-25MP ) is used for this model.   Another model has a Cx486SLC/3-33MP ( 33MHz unit )
     on the PCB.    Most probably, these Cyrix 386 CPUs have 1KB L1 cache.

*  "UGT" label observed in pictures means "Upgrade Technology Co. Ltd". It was a well known developer of  upgrading parts mainly for PS/55.  The company imported upgrade products made by Evergreen and Kingston and they made some modification for those products. 

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