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 233
     TurboChip 400
   Evergreen Spectra 233/400
   Buffalo HP5-MMX300L

Clock and Multiplier Selection Pins (BF1 and BF0)
   Intel Pentium
   AMD K6

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 Sandy. Edited by Major Tom.


Interposers

Evergreen (Photo by 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

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

CPU Control Panel ("CCP") (Windows 95/98/NT)

A software utility that displays information about your CPU, Motherboard, Chipset, and BIOS. It enables you to configure your CPU settings.

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

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

PL-54C/MMX (manual)

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.

PL-OD54C

Upgrade for P75/90/100 systems to P133 to P200 (Non-MMX Upgrade).
Voltage regulator is not used. This interposer provides clock multiplying jumpers for BF1 which is omitted in P75/90 systems. Very simple and easy to use. Actually speaking you don't need this interposer for upgrading P75/90 to classic Pentium 133-200, if you don't care for soldering rework of a planar.
Check Peter's P90 tuning page for the method.

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

PL OD54C

Switch Settings

SW1 Core/Bus Frequency Ratio
P1 P2
OFF
OFF
1.5 x
OFF
ON
2.0 x
ON
ON
2.5 x
ON
OFF
3.0 x
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 )

I got this unit very cheep planing to use it for 8640. Back in home, pulled off the outer case of Server 320, set a K6-233 onto the interposer securely and attempted to place it onto the socket on the planar....A huge heat sink sit in front of CPU sockets BLOCKED the interposer.
For P90 "Y" complex, you have to rearrange fins of LT11084 heatsink so that you can set the interposer on the socket properly.

This unit looks like with an Evergreen's CPU adapter introduced in Tam's page.

When I got Server 500, This one could have it's home for a while. Yes, just for a while.
I bent two of the pins when I pushed it onto the socket while I tested CPUs including MMX 233. One of the bent pin was finally torn off when I tried to straighten it. Grrr... Broken Arrow, that's it.

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 (manual)

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 (manual)

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 6 x *1 5.5 x 5 x 4.5 x 4 x 3.5 x 3 x 2.5 x 2 x
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 (manual)

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 (manual)

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. here.

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 6 x 5.5 x 5 x 4.5 x 4 x 3.5 x 3 x 2.5 x 2 x
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 (Photos by Jim Hall, Explanation by Jim)

"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.

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

JP1 JP2 JP3 Speed
OPEN 1-2 1-2 x 2.5
OPEN OPEN 1-2 x 3.0
OPEN OPEN OPEN x 3.5
1-2 1-2 OPEN x 4.0
1-2 1-2 1-2 x 4.5
1-2 OPEN 1-2 x 5.0
1-2 OPEN OPEN x 5.5
1-2 1-2 OPEN x 6.0
x 6.0 is not documented, but theoretically...

Vcore Voltage setting

JP5 JP4 Vcore
OPEN 1-2 2.2V
OPEN 2-3 2.8V
1-2 OPEN 2.9V
2-3 OPEN 3.3V
Combination of JP5/OPEN and JP4/1-2 listed topmost column is printed as 2.1V on the PCB but 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 Page
German Page
Jumper Settings


Upgrade Kits

Kingston

TurboChip 233 (guide)

Kingston TurboChip 233 uses Intel MMX233 CPU.

Features:

  • Powerful Intel® MMX enhanced microprocessor running at
  • 233MHz processing speed.
  • 32KB Level One (L1) Cache
  • Onboard voltage regulator to interface with either 2.8V or 3.3V 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 200

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

TurboChip 400 (guide)

Turbochip 400 uses K6-II/400 CPU. 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 233 (manufacturer)

Not sure which CPU this unit uses, Intel MMX233 or K6. Anyway "233" means it may not work on Y complex.

There were several models rated 300 MHz to 400 MHz using K6-II CPUs like Kingston TurboChip.

I'm not sure but it seems Spectra upgrades do not have clock multiplier jumpers and they automatically set it to Max rating provided with the CPU used.

Buffalo HP5-MMX300L

CPU accelerator by Buffalo. Mobile MMX300 assembled on a PCB for PGA Socket 5/7.

Intel CPU is used for this accelerator. But Y complex can't boot with it. Works fine for 6886 planar so far.


Clock and Multiplier Selection Pins (BF1 and BF0)

Intel Pentium (from 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 (from 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 Ohland, Peter Wendt, William Walsh, David Beem, Tatsuo Sunagawa, Jim Shorney, Tim Clarke, Kevin Bowling, Tomáš Slavotínek, and many others.

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