Pentium Processor Upgrade

Draft # 1.  2002.11.02 
Draft # 3.  2002.11.16
Updated   2002.12.02 


 Processor Upgrade kit
  TurboChip 233
  TurboChip 400

  Spectra 233/400

 Interposer Sec. 2
  PL-MMX Ver.2.01V
  PL-ProMMX Ver.3
  PL-ProMMX Plus
  PL-ProMMX Plus Ver.4.0

 BF1 and BF0
 Core/BUS Frequency ratio

P54CT    Pentium Overdrive 
P55C       MMX Pentium P55CTB  MMXPODP


Cyrix &  IDT

When you  use AMD K6-II CPUs rated higher than 350MHz for your system running Windows 95B or 95C,  you need  amdk6upd.exe

P55C-K6-S1   Photos are donated 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  Over View on Type Y

#4  Jumper Block # 5  Setting Instruction System Requirement:

#6 Proud 90MHz of Jim's 95

 VCORE Voltage setting
 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 colum is
  printed as 2.1V on the PCB but 
  supplement sheet says it was 
  changed to 2.2V on  -S1.
 For  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 designated, but

ALL pictures are captured by Jim Hall 

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 P-166 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 GenuineI ntel.
        Type ID = 0
        Family ID = 5
        Model ID = 2
        Stepping ID = 12
        Clock Frequency, Internal = 180 MHz "

Careful with that axe, Eugene.  Connection pins for SPGA socket are shorter than the others.

TurboChip 233   ( install guide in pdf format)
Kingston TurboChip 233 uses Intel MMX233 CPU. 
  Special Features
  Your Kingston TurboChip 233 includes these important 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 uses AMD K6 200MHz.  Most possibly,  It will be kicked out by system BIOS of Y complex.

TurboChip 400   ( install guide in pdf format)
  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. 


Spectra 233
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 300MHz  to 400MHz using K6-II CPUs like Kingston TurboChip.
I'm not sure but it seems Spectra upgrades do not have clock multipling jumpers and they automaticaly set 
it to Max rating provided with the CPU used..


Clock Multiplier 

from AMD K6 manual  21850.pdf 

4.10        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 Table 18. BF[2:0] have weak internal pullups and
               default to the 3.5 multiplier if left unconnected.

            Table 18. Processor-to-Bus Clock Ratios
State of BF[2:0] Inputs
Processor-Clock to Bus-Clock Ratio
2.0x or 6.0x*
* 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

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