Pentium Interposers and Upgrades


Interposers
   Evergreen
   PowerLeap
     CPU Control Panel ("CCP")
     PL-54C/MMX
     PL-OD54C
     PL-MMX v2.01V
     PL-ProMMX (SVRM) v4.0
     PL-ProMMX (SVRM) v6.0
     PL-ProMMX Plus old version
     PL-ProMMX Plus v3.0
     PL-ProMMX Plus v4.0
     PL-K6-III
   Zerus P55C-K6-S1
   Madex Interposers
Upgrade Kits
   Kingston
     TurboChip 200
     TurboChip 233
     TurboChip 366 & 400
   Evergreen
     Spectra 233
     Spectra 333
     Spectra 400
   Buffalo HP5-MMX300L
Clock and Multiplier Selection Pins (BF1 and BF0)
   Intel Pentium
   AMD K6

Important: If you are planning to use AMD K6-2 CPU rated higher than 350 MHz for your system running Windows 95B or 95C you need amdk6upd.exe.

Content created by Tatsuo "Sandy" Sunagawa and Tomáš "Major Tom" Slavotínek.


Interposers

Evergreen

Photos thanks to MadMax.

Switch Settings

CLK
MUL
P55C, M2, K6
(DUAL VOLTAGE)
P54C, K5
(SINGLE VOLTAGE)
3.5 (1.5)
3
2.5
2
P1
OFF
OFF
ON
ON
P2
OFF
ON
ON
OFF
P3
OFF
OFF
OFF
OFF

CLK
VCC
P55C, M2, K6 6X86L
SOCKET 5 (5V)
P54C, K5, 6X86
SOCKET 7 (3.3V)
P4
ON
OFF

CORE
VCC
P54C, K5
6X86 3.3V
K6 3.1V
P55C, M2
6X86L 2.8V
M2 2.5V
P5
ON
OFF
OFF
OFF
P6
OFF
ON
OFF
OFF
P7
OFF
OFF
ON
OFF
P8
OFF
OFF
OFF
ON

DIP switch settings to run a 233MMX chip:

P1 P2 P3 P4 P5 P6 P7 P8
OFF OFF OFF ON OFF OFF ON OFF

PowerLeap

Official Website (archived)

Troubleshooting Guide for PL-ProMMX and PL-ProMMX Plus.

US5919259 Method and apparatus for supplying power to a CPU using an adaptor card (Google)
US5938769 CPU escalating adapter with multivoltage and multiple frequency selection (Google)

CPU Control Panel ("CCP")

A software utility that displays information about your CPU, Motherboard, Chipset, and BIOS. It enables you to configure your CPU settings. Supports Windows 95/98/NT.

CCP 5.1.0.1 (1.32MB)
CCP 5.0.0.27 (1.31MB)
CCP 4.0.0.29A (960KB)
   Last updated: Oct 2000
CCP 4.0.0.29 (960KB)
CCP 4.0.0.28 (940KB)
CCP 4.0.0.27 (680KB)
CCP4015.EXE (775KB)
CCP4013.EXE (863KB)
CCP403.EXE (837KB)
CPUPANEL.EXE (657KB)
   Version 3.0, Last updated: Dec 1998. Includes support for PL/586 write-back cache.
SETUP.EXE (510KB)
   Version 2.0, Last updated: Oct 1997

Using the PL-Pro/II Utility Software
User's Guide for CPU Control Panel Utility

PL-54C/MMX

PowerLeap PL-54C/MMX Installation Guide

Can be used to upgrade systems with Socket 4 (original 5V Pentium) to Socket 5/7 CPUs.

Not tested, but it should fit the Type 4 "P" and "Q" processor boards.

Photos thanks to MadMax.

PL-OD54C

Upgrade for P75/90/100 systems to P133 to P200 (Non-MMX Upgrade).
Doesn't have a voltage regulator. It only provides clock multiplier jumpers for pin BF1 which is omitted in P75/90 systems. Very simple and easy to use. You actually don't need this interposer to upgrade P75/90 to classic Pentium 133-200, if you don't mind reworking the board (check Peter's P90 tuning page for the method).

PL OD54C

This one can be used on the Type 4 P90 "Y" complex.

Switch Settings

SW1 Core/Bus
Frequency Ratio
P1 P2
OFF
OFF
1.5x
OFF
ON
2.0x
ON
ON
2.5x
ON
OFF
3.0x
P1 connected to BF1 (Pin X34)
P2 connected to BF0 (Pin Y33)

PL-MMX v2.01V

Upgrade for Pentium 75-200 to MMX Pentium, K6 and M2.
Available CORE VCC; 3.3V, 3.1V, 2.8V, 2.1V
Maximum CORE/BUS ratio is 3.5 x (MMX 233 & K6-2 333)

This interposer won't fit on the Server 320 planar because of a large heatsink that sits in front of the CPU sockets.
It will work on the P90 "Y" complex, but you will have to bend fins of the LT11084 heatsink to make enough space for the interposer.

Tam's take on using this interposer with the T4 Y complex can be found HERE.

Physical Compatibility

PC Server 320 8640-Mxx No
Type 4 Y (P90 complex) Rework needed
PC750 6885/5886 ?

SW1:P1 OFF OFF ON ON
SW1:P2 OFF ON OFF ON
RATIO 3.5/1.5
3
2
2.5
CPU
P55C, M2, K6 (P54C, K5)
RATIO
3
3
2
2
CPU
6X86, 6X86L
CLK VCC Socket 5 5V Socket 7 3.3V
SW1: P4 ON OFF
CORE VCC 3.3V 3.1V 2.8V 2.5V
SW1: P5 P6 P7 P8
CPU P54C K6 *1 P55C M2
*1 Some of K6-233 are rated 2.2V VCC

PL-ProMMX (SVRM) v4.0

It looks like PL-ProMMX Plus (below). Two capacitors are placed around Pin 1 (front edge) but the switch block is placed inside the Socket at CPU side like PL-MMX listed above.

Physical Compatibility

PC Server 320 8640-Mxx Main CPU socket only
Type 4 Y (P90 complex) Rework needed. Not recommended.
PC750 6885/5886 Yes

PL-ProMMX (SVRM) v6.0

PowerLeap PL-ProMMX Installation Guide - ver. 6.xx

Looks similar to PL-ProMMX Plus v4.0. No capacitors at the pin 1 side, switch block on the TOP side, inside the CPU socket.

Not tested, but it should fit to PC Server 320 (both CPU sockets), P90 complex, PC750 and other machines.

PL-ProMMX Plus old version

PowerLeap PL-ProMMX Plus Installation Guide

Upgrade for Pentium 75-200 to Intel MMX233 and (up to) K6-2/366.
Covers Core Vcc from 1.6V to 3.5V with 0.1V stepping.

JP2, Jumper blocks for Core Vcc setting, and a can type capacitor locates in front of Pin 1. Overhang of PCB for these parts hits the Voltage regulator in front of 2nd CPU socket of 8640/MCA planar.
NO, it does not fit to 8640-MYR. It doesn't fit to the 2nd CPU socket but DOES fit to the 1st socket.
It can be used for PC750 too.

Physical Compatibility

PC Server 320 8640-Mxx Main CPU socket only
Type 4 Y (P90 complex) Rework needed. Not recommended.
PC750 6885/5886 Yes

Front View (right)

Jumper Block for Core voltage settings and a capacitor in front of the PCB may interferes with a heatsink of voltage regulator on a 8640-Mxx 2nd CPU socket and on a Type 4 Y P90 complex.

Bottom View (left)

Silkscreened "PL-ProMMX Plus REV 2.1"

Rear View (right)

JP1 Settings: Clock Multiplier

P55C, K6, K6-2, 6x86L, 6X86MX, MII (Dual Volt), C6, P54C (Single Volt) 6X86 *2
CLKMUL 6x *1 5.5x 5x 4.5x 4x 3.5x 3x 2.5x 2x
Pin 1-2 Closed Open Open Closed Closed Open Open Closed Closed
Pin 3-4 Open Open Closed Closed Open Open Closed Closed Open
Pin 5-6 Open Closed Closed Closed Closed Open Open Open Open
*1: 6x setting is not listed in the installation guide.
*2: For 6x86 (Single-Voltage) and 6X86L (Dual Voltage)

JP2 Settings: CPU Voltage and Overheating Protection

CPU Type C6
WinChip
P54C K6-233 *1 K6-200
6x86MX
P55C
6X86L
K6-266/300
K6-2
K6-3 *2
Core Voltage 3.5V 3.3V 3.2V 2.9V 2.8V 2.2V 1.8V
JP2: Pins 1-2 Closed Closed Open Closed Open Open Closed
JP2: Pins 3-4 Closed Open Open Open Open Closed Closed
JP2: Pins 5-6 Closed Closed Closed Open Open Open Open
JP2: Pins 7-8 Closed Closed Closed Closed Closed Open Open
JP2: Pins 9-10 Closed Closed Closed Closed Closed Closed Open
*1 Check carefully actual voltage printed on the Chip. Some are rated 3.2V and the others are rated 2.2V.
*2 K6-3 is listed in the guide book. I myself have not yet tested K6-3 with this interposer.

Pins 11-12: CPU Overheating Protection)

JP2: Pins 11-12 Overheating Protection
Closed
Enabled
Open
Disabled

PL-ProMMX Plus v3.0

PowerLeap PL-ProMMX Plus Installation Guide - ver. 3.xx

The PCB extends only to one side of the socket, similar to version 4.0. However the switches are on the TOP side of the board, inside the replacement CPU socket, rather than on the underside.

See PL-ProMMX Plus v4.0 for system compatibility info.

PL-ProMMX Plus v4.0

PowerLeap PL-ProMMX Plus Installation Guide - ver. 4.xx

Note: This model was later sold as just PL-ProMMX Plus sans the version number. So you better check how it looks, if you are planning to use it for the Type 4 "Y" P90 complex. The older version with the same name may not fit the complex. The latest model was sold with a heat sick/fan combo which is different compared the one pictured below.

Can be used to upgrade Pentium 75-200 systems to Pentium MMX 233, K6-2/400-450, and other newer CPUs. Wide selection of core voltages that covers most of Intel, AMD (except K6-III), IBM/Cyrix and IDT CPUs.

This one can be used for PC Server 320 8640 (both CPU sockets), Y complex, and PC750 6885/6886. No capacitor nor jumper block is located on the side with pin 1, thus the interposer doesn't interfere with the voltage regulator heatsink of the 320 planar and Y complex.

Physical Compatibility

PC Server 320 8640-Mxx Yes (both sockets)
Type 4 "Y" (P90 complex) Yes
PC750 6885/5886 Yes

Core voltage regulation is driven by the Fairchild RC5057 DC-DC Controller.

Power Supply Connector

Connector specs: 3-pin, 3.96 mm pitch, 1.14 mm square pin. Available from many different manufacturers, e.g. JST's VH series.

Pinout of the male connector soldered to the interposer PCB (top view, pin 1 closer to the CPU socket):

PinDescription
1+5 V
2Ground
3+12 V

Switch Setting

SW1: Pins 1, 2 & 3 for Clock Multiplier

P55C, K6, K6-2, 6X86MX, MII (Dual Volt), C6, WinChip2, P54C (Single Volt) 6X86 *1
CLKMUL 6x 5.5x 5x 4.5x 4x 3.5x 3x 2.5x 2x
Pin 1 ON OFF OFF ON ON OFF OFF ON ON
Pin 2 OFF OFF ON ON OFF OFF ON ON OFF
Pin 2 OFF ON ON ON ON OFF OFF OFF OFF

SW1: Pins 4, 5, 6, 7 & 8 (Core Voltage)

CPU Type C6
WinChip
P54C
6X86
K6-233 * K6-200
6x86MX
MII
P55C
6X86L
K6-2/450 K6-266
K6-300
K6-2
Core Voltage 3.5V 3.3V 3.2V 2.9V 2.8V 2.4V 2.2V
SW1: Pin 4 ON ON OFF ON OFF OFF OFF
SW1: Pin 5 ON OFF OFF OFF OFF OFF ON
SW1: Pin 6 ON ON ON OFF OFF ON OFF
SW1: Pin 7 ON ON ON ON ON OFF OFF
SW1: Pin 8 OFF OFF OFF OFF OFF OFF OFF
* Check carefully actual voltage printed on the CPU label.
(there are two types in K6-233, different core Vcc)

* You can set Core Voltage to another value not listed in above diagram.
From 1.30 V to 2.00V by 0.05V stepping and from 2.0V to 3.5V by 0.1V stepping.

SW1: Pin 10 (CPU Overheating Protection)

SW1: Pin 10 Overheating Protection
ON Enabled
OFF Disabled

SW1: Pin 9 - No comment for Pin 9 in the associated Manual. But there is a instruction for this pin SW in Installation Guide PDF for PL-K6-III. Don't know if Pin 9 actually works for this model or not. At least, in all sample diagrams for CPU setting show this pin in OFF position.

From PL-K6-III PDF:
   SW1: Pin 9 (Pin AL-1 Compatibility) Pin 9 of SW1 lets you enable/disable the pin signal for split-voltage detection. This function provides compatibility for certain HP Vectra and Biostar systems that check the signal.
   For split-voltage CPUs, certain HP Vectra (VL100 and VL5/133 Series 5 DT) systems and certain Biostar motherboards (8500TUD and M5ALA) check for the presence of a signal from pin AL-1. Unfortunately, these systems use the AL-1 pin signal differently: the signal must be disabled in order for the HP Vectra systems to function properly, while the Biostar motherboards need to detect the signal in order to boot.
   If your HP Vectra or Biostar system does not run properly with the PL-K6-III installed, try using pin 9 of the SW1 DIP switch to turn the AL-1 pin signal on/off. Pin 9 is set to ON by default--this setting allows Biostar systems to detect the pin signal and boot. For HP Vectra systems, changing the switch setting to OFF will disable the signal and allow the system to function. Most systems (including most HP Vectra systems and Biostar motherboards) will be unaffected by the pin AL-1 setting.

Pin 9: Pin AL-1 Compatibility

SW1: Pin 9 AL-1 Compatibility
ON Pin Connected
OFF Pin Disconnected

PL-K6-III

A further development of the PL-ProMMX Plus interposer. It brings official support for the AMD K6-III chips.

Multiple different revisions:

PL-K6-III/98 version 1.0
PL-K6-III version 2.1
PL-K6-III version 2.2
PL-K6-III version 2.3

Zerus P55C-K6-S1

"For those of you who haven't seen this upgrade, it consists of an interposer similar to the Madex, with a plug for a power tap used on 3 1/2" clone style floppy drives to handle the power requirements of the Intel (or any pin compatible) CPU. The cooling fan also draws its power from the same source."

Exactly the same product was also sold in Japan before. it was named as "Multimedia CPU Upgrade Kit". It was made of Taiwan and marked as "CE". I don't know this "CE" logo which can be seen many computer products manufactured in Taiwan.

Photos by Jim Hall, explanation by Jim.

1) Close View 2) Bottom View 3) On the Type 4 "Y"

4) Jumper Block 5) Jumper Settings 6) Jim's Proud 90MHz M95

Specifications

Socket 5 or 7
Voltage Supplied: 2.2V, 2.8V, 2.9V, 3.2V
Current rate: 15A for P55C-K6-S
Connection: 320 pin SPGA

Multiplication Jumper Setting

2.0x
6.0x
2.5x3.0x3.5x4.0x4.5x5.0x5.5x
JP1OpenOpenOpenOpen1-21-21-21-2
JP21-21-2OpenOpen1-21-2OpenOpen
JP3Open1-21-2OpenOpen1-21-2Open
The 5.0x and 5.5x option is not marked on the PCB (only in manual?).
The 2.0x/6.0x option is not documented at all, but should work.

Vcore Voltage setting

2.2 V2.8 V2.9 V3.2 V
JP41-22-3OpenOpen
JP5OpenOpen1-22-3
Combination of JP5 Open and JP4 1-2 is marked as 2.1 V on the PCB,
but the supplement sheet says it was changed to 2.2V on -S1.

3.3V single voltage for I/O and Core is not designated. Thus Jim set Core voltage to 3.2V and put his classic Pentium P166 with 3x speed jumper setting and set it on his Y complex. Y complex has 60 MHz OSC so his system actually run at 180 MHz.

Report to the news group from Jim Hall:
   "OK, ran a little windows program called CPU id, by Alexander Berezkin. It identifies the CPU as an Intel Pentium, brand name Genuine Intel.
Type ID = 0
Family ID = 5
Model ID = 2
Stepping ID = 12
Clock Frequency, Internal = 180 MHz"

Madex Interposers

Information about Madex Interposers for Socket 5 and 7 systems:

English: Product Page, Jumper Settings
German: Product Page, Jumper Settings (has some extra info)


Upgrade Kits

Kingston

TurboChip 200

TurboChip 200 User's Guide

TurboChip 200 uses AMD K6 200 MHz. Most possibly, It will be kicked out by system BIOS of Y complex.

TurboChip 233

TurboChip 233 User's Guide

Kingston TurboChip 233 uses Intel Pentium MMX 233 CPU.

Features:

  • Powerful Intel® MMX enhanced microprocessor running at 233 MHz processing speed.
  • 32 KB Level One (L1) Cache
  • Onboard voltage regulator to interface with either 2.8 V or 3.3 V system motherboard automatically.
  • Supports multimedia extensions instructions
  • "Plug and Play" installation. No software drivers to install.

Unfortunately TurboChip 233 does not have CPU speed jumper and it will automatically set the clock multiplier to 3.5x. It is supposed that TurboChip 233 may not run on Y complex. Any experience?

TurboChip 366 & 400

TurboChip 366 User's Guide
TurboChip 400 User's Guide

Turbochip 366 and 400 uses K6-2 clocked at 366 and 400 MHz respectively. Needless to say it's incompatible with Type 4 "Y" complex.

But it may run in PC Server 320/520 or PC750 6886.

Evergreen

Spectra Default Jumper Settings Page (alt) (archived)

Evergreen Spectra Install Disk (zipped image) (thanks to Christian Holzapfel)

Spectra 233

Spectra 233 Support Page (alt) (archived)
Spectra 233 White Paper Page (archived)

Spectra 233 is based on the IDT WinChip 2 233 MHz processor.
Seems like later releases used Intel Pentium MMX 233 MHz (pictured below).

Photos thanks to "Cyrix200+".

Spectra 333

Spectra 333 Support Page (archived)
Spectra 333 White Paper Page (archived)

Spectra 333 is based on the AMD-K6-2 333 MHz processor.

PCB marked as "P55C-K6-S2". Very similar to Zerus "P55C-K6-S1", but the "-S2" adds JP6 for additional voltage settings.

More photos: right, left, jumpers, heatsink #1, heatsink #2 (all photos thanks to "tkrn's archive")

Multiplication Jumper Setting

2.0x
6.0x
2.5x3.0x3.5x4.0x4.5x5.0x*5.5x
JP1OpenOpenOpenOpen1-21-21-21-2
JP21-21-2OpenOpen1-21-2OpenOpen
JP3Open1-21-2OpenOpen1-21-2Open
* Default setting

Vcore Voltage setting

1.8 V2.2 V*2.4 V2.8 V2.9 V3.2 V
JP4Open1-2Open2-3OpenOpen
JP5OpenOpenOpenOpen1-22-3
JP61-2Open2-3OpenOpenOpen
* Default setting

Spectra 400

Spectra 400 Support Page (archived)
Spectra 400 White Paper Page (archived)

Spectra 400 is based on the AMD-K6-2 400 MHz processor.

Buffalo HP5-MMX300L

CPU accelerator by Buffalo. Features Mobile Intel Pentium MMX @ 300 MHz on a PCB with a Socket 5/7 plug.

The Y complex can't boot with it. Works fine in the 6886.


Clock and Multiplier Selection Pins

This section discusses the behavior of the BF0, BF1, and BF2 (AMD-only) clock multiplier selection pins.

Intel Pentium

Source: Intel Documents

Multipling Pins

CPU Signal Pin Active Level Synchronous/
Asynchronous
Internal Register
P54C BF0 Y33 HIGH Synchronous/RESET Pull-up
BF1 X34 HIGH Synchronous/RESET Pull-up
P55C BF0 Y33 N/A Synchronous/RESET Pull-down
BF1 X34 N/A Synchronous/RESET Pull-up

BUS Frequency Selection for P54C

BF1 BF0 Bus/Core Ratio Core Frequency (MHz) External Bus
Frequency (MHz)
0 1 1/3 200/180/150 66/60/50
0 0 2/5 166/150/125 66/60/50
1 0 1/2 133/120/100 66/60/50
1 1 2/3 *1 100/90/75 66/60/50
0 0 1/4 *2 266/240/200 *2 66/60/50 *2
*1 Default BUS/Core ratio is 1/2 for P54C.
*2 4x mode was not officially announced by Intel but it is told that some Pentiums with marking of SXxxx and SYxxx have this special Core/BUS ratio.

Early Pentiums (P90 & P75) do not have BF1.

BUS Frequency Selection For P55C

BF1 BF0 Bus/Core Ratio Max Bus/Core
Frequency (MHz)
Min Bus/Core
Frequency (MHz)
0 1 1/3 66/200 33/100
0 0 2/5 66/166 33/83
1 0 1/2 (*1,*2) N/A (2) N/A (2)
1 1 2/7 66/233 33/177
*1 This is the default bus to core ratio for the Pentium processor with MMX technology. If the BF pins are left floating, the processor will be configured for the 1/2 bus to core frequency ratio.
*2 Currently, there are no products that support these bus fractions.

AMD K6

Source: AMD K6-2 Data Sheet

BF[2:0] (Bus Frequency) - Inputs, Internal Pullups

Summary: BF[2:0] determine the internal operating frequency of the processor. The frequency of the CLK input signal is multiplied internally by a ratio determined by the state of these signals as defined in the Table below. BF[2:0] have weak internal pullups and default to the 3.5 multiplier if left unconnected.

Processor-to-Bus Clock Ratios

BF[2:0]
State
Processor-Clock
to Bus-Clock Ratio
100b 2.5x
101b 3.0x
110b 2.0x or 6.0x*
111b 3.5x
000b 4.5x
001b 5.0x
010b 4.0x
011b 5.5x
*The ratio selected is dependent on the stepping of the Model 8.
The 2.0x ratio is supported on the Model 8/[7:0],
whereas the 6.0x ratio is supported on the Model 8/[F:8].

Sampled: BF[2:0] are sampled during the falling transition of RESET. They must meet a minimum setup time of 1.0 ms and a minimum hold time of two clocks relative to the negation of RESET.

Content created and/or collected by:
Louis F. Ohland, Peter H. Wendt, David L. Beem, William R. Walsh, Tatsuo Sunagawa, Tomáš Slavotínek, Jim Shorney, Tim N. Clarke, Kevin Bowling, and many others.

Ardent Tool of Capitalism is maintained by Tomáš Slavotínek.
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