SuSE Support Database
Title: General hardware problems

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General hardware problems
Symptom:
One ore several of the following phenomena occur :
- Timing problems when accessing the CD-Rom (halt,long delays, bus errors, segmentation faults)
- kernel generation (or compilation of other programs) aborts with signal 11
- kernel generation (or compilation of other programs) aborts with signal 7
- Incorrect file content
- Memory access errors
- Graphics is not displayed correctly
- crc-erros when accessing the floppy disk drive
- Crashes or halts during boot-up
- Errors when crating a filesystem (mke2fs reports errors)
Cause:
These strange phenomenons are to be explained for sure
either by faulty or extremely sharp configured hardware.
The reason for this is that many motherboards apparently have
timing problems. These timing problems become visible through
bus errors (CPU-memory-PCI-ISA).
Even if the system works stable under e.g. DOS or Windows, this
doesn't mean anything for the stability of the hardware
and its configuration. The hardware manages to work with the slow
segmentated memory access of a CPU working in 16 bit realmode (under
DOS, Windows). As soon as the memory is accessed linear with 32 bit bursts
errors can occur.
A further cause can be a badly cooled CPU or too slow or faulty (heat-sensitive)
RAM moduls (SIMMS).
So this is for sure caused by the hardware and not by Linux.
Linux requires more hardware stability than other operating systems do.
On one hand this way a higher performance can be achieved. On the other hand
this can lead to the above mentioned problems on some systems. In contrast to
other operating systems Linux assumes that the hardware works stable. If this
is not the case Linux stops working.
An operating system that still runs with faulty or potentially faulty
hardware represents a severe security risk.
Remedy
There are a couple of parameters and conditions that can be changed
in order to isolate the faulty equipment.
- Switch off the internal and/or external Cache using the BIOS setup (CMOS)
- Reduce bus clock (VLB maximum 40MHz !
PCI bus according to the specification maximum
66 MHz ext. processor clock) : use BIOS setup or jumpers on the mainboard.
- Add waitstates : use BIOS setup
- In (Advanced) Chipset Setup, if available,
set
CAS before RAS
: Use BIOS setup
- Thest the memory :
- Particularly using different chip or modul types will lead to problems
- When using a PCI-bus with 66 MHz the DRAM modules must
be specified with 60ns or less (no overtiming).
- Check the fixture of the SIMMS or DIMMS, they must fit exactly and must
not be loose or tilt. Remove the modules from the board and put them back in
(corroded contacts).
- Change the order of the modules and memory banks.
- Check that the CPU fan is working and whether it really fits
exactly on the CPU (if necessary use heat transfer paste)
- Switch off Power Management (APM). This was noticed several times,
particularly in conjunction with the 2940 : Use the BIOS setup.
- Some Pentium clones cause problems if the kernel or the compiler were
optimized for the Pentium but a K6 or a Cyrix 6x86 is used instead.
On such a system you have to optimize the kernel and the
programs for a 486 at the maximum. It might even be necessay to fall back to
386 optimization.
- Check all general BIOS settings. If necessary fall back to the (rather
conservative) BIOS defaults.
- If you have a buggy PC-BIOS the only solution is a BIOS update.
Ask your local dealer or the manufacturer of the mainboard. See also the article
"Motherboard Chaintech 5IFM-0 causes problems" maddin_ifm0.html
- The power supply doesn't supply enough eletricity or the voltage fluctuates : Try to switch off
some devices.
Further information:

See also:

Keywords: HARDWARE, APM, 2940, INCONSISTENT DATA, INEXPLICABLE, SIG11, SIGNAL11, SEGMENTATION FAULT, POWER MANAGEMENT, MKFS, MKE2FS, CRC

Categories:
Frequently asked Questions
, Hardware

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SDB-kfr_58, Copyright SuSE GmbH, Nuremberg, Germany
- Version: 12. Mar 1998
Impressum - Last generated: 24. Feb 1999 14:56:20
by maddin
with sdb_gen 1.00.0