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Xgaopt.exe Installs updated ('92) SC.EXE, XGA/2, SCSI, SCSI w/cache ADFs, plus updated *.dgs. For 5565, 5657, 70486, 7080, 7677, 90, 95, P70, P75. 70bios.dsk (720K) ECA 092: 8570 Data Modification Patch 188-078 PS/2 MODEL 70 386 (8570-A21) 189-196 PS/2 MODEL 70 486 (8570-B61 AND 8570-B21) 189-102 PS/2 486/25 Power Platform The 386 -A61 and -A21 can be upgraded by a 486/25 Power Platform. It uses the same planar, but the processor card has a 386 and a socket for a 387DX. The only 486 system that supports memory expansion adapters is the model 70 A21 BIOS Images. Use AM27C512-175 C/T or equivalent. Axx 386 BIOS 33F9987 Odd / 33F9988 Even Bxx 486 BIOS 64F3125 Odd / 64F3126 Even Additional
Standard Power Connector 25MHz Planar
25 MHz Planar Axx series shown 
Axx BIOS 33F9987 Odd, 33F9988 Even Keyboard Fuse? PTC (?) marked "221K 100V" in the yellow-brown one
associates with a Bourne product. Searching brings up a
capacitor, maybe this was a fix for a keyboard or mouse
port issue? E1 Jumper Outline Memory You can use 65X5806, 65X5806D, or Micron DC 2391 (or is
that MBBY9?). The IBM stuff has "masked" SIMMs, where R3
and R4 positions are under the PCB resist. You can only
find R1 (open) and R2 (shorted) on the IBM 2MB 80nS
SIMMs. Third party SIMMs (like Micron) may have all four
PD bit positions available, with R1 open, R2 and R3
shorted, and R4 open. Further Memory Struggles The SIMMs should be installed
beginning with J21 and/or J20. I got 215 errors (bad
SIMM configuration or timing? And it occurs immediately
before any counting, like the 225 error) when starting
with J17 or J18 and a single true IBM FRU 92F0104 P/N
6450608 2MB 80ns Parity SIMM. 8570-25MHz Models GRAPHICS J19 Header is Edgecard NOTE: If you look
above J19, there are solder pads for J19A, which may
have been for the older Speaker/Battery assembly. ECA 029 8570-Axx, Bxx Bus Master Errors Some 25MHz system boards may have problems with BusMaster cards like the IBM SCSI adapter as well as others (AOX). If the card fails to operate properly, examine the barcode label on the system board. If the board has a prefix of B1HC"A", through B1HC"H", replace the board with Part Number 15F7657. [ed. if you can...] ECA 021 - 8570-A21 110
error PHYSICAL CHECK: This ECA applies to all 25MHz 8570 systems that contain an 80MB or 160MB hardfile that are running DOS or OS/2. The 8570s that contain those hardfiles are Models A81 and A16 and upgraded 486 Models B81 and B16. . It is provided to address a potential problem related to the transfer of data from the hard disk. SEE ECA092. 70bios.dsk (720K) Installs abios file for use under OS/2 or DOS only.
The original pics for the Power Platforms came from Pete Rickard. Thanks! (Damn hard holding on to the bottom of the earth when typing!) 386
Power Platform FRU
15F7659 J1, J2 Reverse of
header Axx
BIOS Bxx Series BIOS Bxx 486 BIOS 64F3125 Odd / 64F3126 Even 486/25
Power Platform FRU
64F0123 (?) NOTE:
Don't be surprised if your 486 Processor board has
yellow rework wires on it, mine does and it is marked
"Good".  Original image from ebuy
seller nyce-distribution.
486/25 Power Platform Trivia
Upgrade Bxx Series From Tam Thi Pham It *is* possible to beef up the Model 70, with just a tad bit of work. The 8570-B21 will run the Kingston Turbochip (133MHz) nicely if you upgrade the crystal on the CPU card to 66MHz. There's a slight issue with clearance for the CPU fan, and it requires that you shave away a bit of plastic from the underneath side of the top-level drive mounts. Either that, or you could fabricate your own low-profile heatsink device of some sort. I'm still figuring out all the logistics for an elegant solution. Now, the heatsink on the 486DX2-66 Overdrive already has a nice low-profile, and allows that chip to mount in directly as is for an easy upgrade. I'm thinking you'd rather go all the way to 133MHz, though. Please keep an eye out on the newsgroup (and my site, probably) and I'll detail my Model 70 upgrade experience. |
