Still Crazy

980700 - BIOS Modification (Type-A, Type-B, and Other Models)

The story is a bit long so let's make the long story short. I got reprogrammed BIOS ROMs for Type-A and Type-B complex. Type-A, the fastest complex among all of PS/55 complexes, got boosted further with 80MHz OSC and a BIOS ROM. Free from 102 error, with an AMD 5x86-133 ADZ on an interposer, 5580-"N" with BooDoo magic'ed Type-A run flawlessly in 160MHz inner speed. "Nancy the second" also had a modified ROM in it and run in 160MHz speed too.

Note: 5551-N uses Flat Packaging Write-One-Time PROM, a tiny SOJ chip. Chip No. is HN 27C301AFP-12 and it belongs to the P571000 series. It's hard to find 27C301 (and other P57C1000 equivalents) these days. P571001 and it's equivalents are common and easy to get. In order to use 1001-type ROM instead of 1000-type, soldering rework is needed to exchange connection of copper traces to pin #2 and pin #24.

CPU WindSock HDBENCH ETDIAG
Model Bus Clock Core Clock CPU Float Integer Dhrystone
5580 with DX2-66 Upgrade Type-A Complex
Intel 486DX4-100 x3 33 MHz 99 MHz 814 37878
AMD 5x86 x4 33 MHz 133 MHz 957 3743 5645 41666
AMD 5x86 x4 40 MHz 160 MHz 1162 4497 6762 51020
5551-NAB
Cyrix 5x86 x3 33 MHz 99 MHz 857 3130 4693
Cyrix 5x86 x3 40 MHz 120 MHz 1017 3752 5643
AMD 5x86 x4 40 MHz 160 MHz 1160 4155 6695 51020
AMD 5x86 x4 42 MHz 168 MHz 1205 4490 6762

CPU & Memory Test Under PFM486 (DOS program)

1) 5551-N 40MHz

 Performance of 486-PC Ver1.77 (C)1992-1994 DysanKeihin
 H----------------------------------------------------H
 | i486Dx Frequency  = 160.26 MHz   Machine:AT   v1.77|
 |    CPUID Results  = AuthenticAMD Fam 4 Mdl14 Stp 4 |
 | Ecache Read Time  =  47 ns/dword ( 6.3wait, 85mb/s)|
 | Ecache Write Time =  80 ns/dword (10.9wait, 50mb/s)|
 | Memory Read Time  =  47 ns/dword ( 6.3wait, 85mb/s)|
 | Memory Write Time =  81 ns/dword (11.1wait, 49mb/s)|
 H----------------------------------------------------H

2) 5551-N Original 33MHz

 Performance of 486-PC Ver1.77h(C)1992-1995 DysanKeihin
 H----------------------------------------------------H
 | i486DX Frequency  = 133.13 MHz   Machine:AT  v1.77h|
 |    CPUID Results  = AuthenticAMD Fam 4 Mdl14 Stp 4 |
 | Ecache Read Time  =  57 ns/dword ( 6.4wait, 70mb/s)|
 | Ecache Write Time =  96 ns/dword (10.8wait, 42mb/s)|
 | Memory Read Time  =  57 ns/dword ( 6.4wait, 70mb/s)|
 | Memory Write Time =  96 ns/dword (10.8wait, 42mb/s)|
 H----------------------------------------------------H

3) 5580-Yx With Souped up Type-A

 Performance of 486-PC Ver1.77h(C)1992-1995 DysanKeihin
 H----------------------------------------------------H
 | i486DX Frequency  = 160.26 MHz   Machine:AT  v1.77h|
 |   CPUID Result    = AuthenticAMD Fam 4 Mdl14 STP 4 |
 | Ecache Read Time  =  47 ns/dword ( 6.3wait, 85mb/s)|
 | Ecache Write Time =  80 ns/dword (10.9wait, 50mb/s)|
 | Memory Read Time  =  47 ns/dword ( 6.3wait, 85mb/s)|
 | Memory Write Time =  80 ns/dword (10.9wait, 50mb/s)|
  H----------------------------------------------------H

4) 8595-J Type-3

 Performance of 486-PC Ver1.77 (C)1992-1994 DysanKeihin
 H----------------------------------------------------H
 | i486Dx Frequency  = 150.00 MHz   Machine:AT   v1.77|
 |    CPUID Results  = AuthenticAMD Fam 4 Mdl 8 Stp 4 |
 | Ecache Read Time  =  26 ns/dword ( 2.6wait,154mb/s)|
 | Ecache Write Time = 179 ns/dword (24.7wait, 22mb/s)|
 | Memory Read Time  = 122 ns/dword (17.0wait, 33mb/s)|
 | Memory Write Time = 179 ns/dword (24.7wait, 22mb/s)|
 H----------------------------------------------------H

Wait! Oh yeah wait a minute Mr.Postman. Wait! Oh No...

5) FYI 9595 Type-4 N Complex

33.333MHz

 Performance of 486-PC Ver1.77 (C)1992-1994 DysanKeihin
 H----------------------------------------------------H
 | i486Dx Frequency  =  66.61 MHz   Machine:AT   v1.77|
 | Ecache Read Time  =  38 ns/dword ( 1.3wait,105mb/s)|
 | Ecache Write Time =  60 ns/dword ( 2.0wait, 67mb/s)|
 | Memory Read Time  = 134 ns/dword ( 7.7wait, 30mb/s)|
 | Memory Write Time =  60 ns/dword ( 2.0wait, 67mb/s)|
 H----------------------------------------------------H

40.0MHz

 Performance of 486-PC Ver1.77 (C)1992-1994 DysanKeihin
 H----------------------------------------------------H
 | i486Dx Frequency  =  79.96 MHz   Machine:AT   v1.77|
 | Ecache Read Time  =  31 ns/dword ( 1.2wait,129mb/s)|
 | Ecache Write Time =  50 ns/dword ( 2.0wait, 80mb/s)|
 | Memory Read Time  = 126 ns/dword ( 8.8wait, 32mb/s)|
 | Memory Write Time =  50 ns/dword ( 2.0wait, 80mb/s)|
 H----------------------------------------------------H

CPUID results were erroneously deleted. But it was a stock DX2-66 with a gold heat sink loaded on my stock N complex.

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