Known Problems
Experience, RETAIN Tips, ECAs, etc.

Here are some known problems and how to solve them (or... not).

Hard-Drive Doesn't Spin up - "Stiction" Issue
Only 16 MB of RAM Available on Systems with SX/SLC CPU

System 36/38 (5250) Emulation Adapter Problems (H062314)
8590 and 8595 50MHz Systems Hang with 36/38 Adapter (H093927)
PS/2 Adapter Installation Restrictions 3270, Token Ring, Etc. (H005662)
Slot 8 Incompatibility in 8595 and 9595 (SF2223)
Failure to Obtain IP Address Via DHCP on Token Ring w/ SP2 (Q163383)


Hard-Drive Doesn't Spin up - "Stiction" Issue (from Peter)

Many older hard-drives tends to hang at Power On. It is a result of adhesive-power between disk surfaces and R/W-heads - so called "stiction". The surfaces are very plain polished and the heads really 'suck' on them. The spindle motor has not enough torque to loosen the platters from the heads. This effect appears sometimes after the computer was off for a longer time (but it can also happen after short period of time, especially if the drive already had the stiction problem before).

There's no 'soft' solution, but here are few options, how to get your drive running again (your mileage may vary):

Option 1:
Several Power On cycles (20 sec. On, then 20 sec. Off) may start the drive... or blow up the power-supply. And is no good treatment for the electronic components at all.

Option 2:
Unplug the system-unit from everything, shake it (up/down several times) then rotate the unit with a sharp kink clockwise some times. Plug it on again and Power on. The heads should have released and the drive spins up.

Don't lift the unit up on the frontside and let it crash back on the desk.
This method will definitely kill your harddisk very soon.

I have had good success with putting the system-unit on the rear seat of my car and drive to town, let the car on a sunny parking lot, go shopping, come back, drive home and plug it back on. Afterwards the drive runs again. Changes of temperature and the vibrations have caused the heads to release from the disk surfaces. Disadvantage: my friend tried the same with his Model 55. Some guys broke his car open and stole the computer.

Option 3:
On some drives you can access the spindle motor if you remove the control board. Then you can very carefully spin the motor (and thus platter inside the HDA), hopefully removing the stiction problem and not snapping the R/W heads in a process.

Important: In either case you have badly treated your Harddisk and it is a good idea to begin backing up the data!

This issue seems to be common on Seagate ST-177I 60MB harddisk used in many Models 55SX (8555-061) and in some Models 70 (70-061).


Only 16 MB of RAM Available on Systems with SX/SLC CPU (from Peter)

In a brief. You can't install more than 16 MB on machines with a 386SX/SLC, 486SLC, SLC2 or SLC3 processor.

"Oh - sure, but my 9556 has a 486!"
"Really? Wasn't it a 486SLC?"
"Uhm... er, yes... think so!"

Gotcha! The 486SLC, SLC2, SLC3 are also 386SX-based chips. Ever wondered why they offer just a 387SX as math co-processor? Now - that's the reason. The 486SLC family has internal L1 cache like a 486 and some of the newer instructions, but externally they are a 386SX. And these have only a 16-bit data bus and 24-bit address bus and thus can only address 16 MB of memory. 24 address lines = 2 ^ 24 bytes of addressable space = 16.777.216 bytes. These processors are from the technical point of view similar to the 286-line CPUs, but have 32-bit registers and other features of 386/486 CPUs, which allows them to run 32-bit software. They can even carry out 32-bit busmaster functions, unless they have only 16-bit MCA connectors (the short ones). But the address-space is limited to 16 MB due to the lack of address lines.

Sad but true.

Tom adds:
   Some SX/SLC systems will recognize memory over the 16 MB limit and show the correct capacity of "Installed Memory" in the "View Configuration" menu of the refdisk. This information is there (probably) only to let the user know that he has more memory installed, than his system can use. The "Usable Memory" line on the same screen shows the amount of memory that is actually available to the operating system and applications.


System 36/38 (5250) Emulation Adapter Problems (H062314)

Symptom

The following problems may be experienced with the Micro Channel 5250 Emulation Adapter.

  1. System hangs with a blank screen at POST (Power-On Self Test)
  2. Host network may hang or fail when the PS/2 (with the affected adapter) is powered-on. Workstations return to sign-on screen after loss of communication.
  3. Running Auto Configuration or Set Configuration results in parity error.
  4. An error of "111 - ?????" during post
  5. Following successful Auto Configuration, the system hangs with meaningless patterns, such as vertical bars, on the screen.

Problem Isolation Aids

Prior to replacing any hardware ensure the latest level corrective service diskette (WSE010003 or later) for System 36/38 Workstation Emulation is installed. This diskette is not necessary if running AS/400 PC support.

Early level System 36/38 Emulation Adapters may be identified by FRU P/N 69X6282, FRU P/N 69X6283 or FRU P/N 69X6292 on the adapter. If one of these adapters is failing in a 95xx system replace the adapter with FRU P/N 69X6294.

Fix

An up-level System 36/38 Workstation Emulation adapter (FRU P/N 69X6294) with option diskette is available from Mechanicsburg parts distribution system.


8590 and 8595 50MHz Systems Hang with 36/38 Adapter (H093927)

Symptom

System hangs may be experienced on 8590 and 8595 systems with a 50 MHz processor and an early version System 36/38 Emulation Adapter installed. The hang condition will only occur during POST (Power-On System Test) or Set Configuration.

If the hang condition occurs at any other time while running the System 36/38 Work Station Emulation Program on the above referenced systems, confirm that PTF #IM00479 (Programming Temporary Fix) is installed.

Problem Isolation Aids

The early System 36/38 Emulation Adapter may be identified by a FRU label on the System 36/38 Emulation Adapter of either: FRU P/N 69X6282, FRU P/N 69X6283 or FRU P/N 69X6292.

Remove the System 36/38 Emulation Adapter to make sure the PS/2 system is operating correctly without the adapter. (Also remove other adapters.)

Fix

The early version System 36/38 (5250 emulation) Work Station Emulation Adapter should be replaced by the current FRU, P/N 69X6294.


PS/2 Adapter Installation Restrictions 3270, Token Ring, Etc. (H005662)

The following list of installation restrictions should be observed when installing the 3270 Connection Adapter, Token Ring Adapter/A, or PC Network Adapter/A in Personal System/2 Models 8550, 8555, 8560, 8565, 8570, 8580 and 9585, to avoid hardware arbitration and interrupt level conflicts: level conflicts:

  1. When installing the 3270 Connection Adapter, it must be located in the lowest numbered slot available, preferably slot #1. The 3270 Connection Adapter uses only interrupt # 2. Refer to TDR #H025467 under D/T3270 for more details.
  2. When installing the Token Ring Adapter/A, it should be in a higher numbered slot than the 3270 Connection Adapter (if present). It should be assigned interrupt #10 or #11 using the reference diskette, "Change Configuration" utility on the "Set Configuration" menu. See caution below.
  3. When installing the PC Network Adapter/A, it must be located in a higher numbered slot than the 3270 Connection and Token Ring Adapters (if present). It should be assigned interrupt level #3 using the reference diskette, "Change Configuration" utility on the "Set Configuration" menu. See caution below. In addition, refer to TDR #H025467 under D/T3270 for more details.

Caution: Once interrupt levels are selected as described above, and have been changed through the "set configuration" utility, they must be saved using the "Backup Configuration" utility on the "Set Configuration" menu. This will protect user selected interrupt levels from being changed to their system default settings when the "Automatic Configuration" utility is executed. Should the automatic configuration utility ever be executed, and the user's previously selected interrupt levels are reset to the system defaults, the user may then execute the "Restore Configuration" utility on the "Set Configuration" menu to restore the interrupt levels to those that were saved with the "Backup Configuration" utility.


Slot 8 Incompatibility in 8595 and 9595 (SF2223)

A 00017100 (171) error occurs on POST (Power-On System Test). This problem may occur on 8595/9595 models xLx or xHx systems during the installation of any of the following adapters in micro channel slot 8:

Fix: Do not install any of the affected adapters in slot 8. Relocate any of the affected adapters to one of the other Micro Channel slots.


Failure to Obtain IP Address Via DHCP on Token Ring w/ SP2 (Q163383)

When you run Windows NT version 4.0, with Service Pack 2 applied, in a source routed Token Ring environment and configured as a DHCP client, you may receive the following message when you start: The DHCP client could not obtain an IP address. If you want to see DHCP messages in the future, choose YES, otherwise choose NO.

Fix: Change the ArpAlwaysSourceRoute value to 1. If this value is not present, click on Edit, Add Value, and enter the following settings: Value Type: REG_DWORD - Boolean Valid Range: 0,1 (False or True) Default: 0 (False).

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.

Ardent Tool of Capitalism - MAD Edition! is maintained by Tomáš Slavotínek.
Last update: 20 Jan 2022 - Changes & Credits | Legal Info & Contact