General Hardware Problems
Support knowledgebase (kfr_58)
Applies to
SuSE Linux: All versions
Symptom:
One or more 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 contents
- Memory access errors
- Graphics are not displayed correctly
- crc errors when accessing the floppy disk drive
- Crashes or halts during boot
- Errors when creating a file system (mke2fs reports
errors)
Cause:
These strange phenomenona are most probably due to faulty or
incorrectly 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 is stable under DOS or Windows, for example, this
does not matter in regards to the stability of the
hardware
and its configuration. The hardware manages to work with the slow
segmented memory access of a CPU working in 16-bit realmode (under
DOS, Windows). As soon as the memory is accessed in linear mode with
32-bit bursts, errors can occur.
A further cause can be a badly cooled CPU or too slow or faulty
(heat-sensitive)
RAM modules.
The real cause is faulty hardware, not the operating system, like
Linux.
Linux requires more hardware stability than some other operating systems
do.
On the one hand, this provides increased performance. On the other hand,
it can lead to the above-mentioned problems on some systems. In contrast
to
other operating systems, Linux assumes that the hardware works properly
and is 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 numerous parameters and conditions that can be changed
to isolate the faulty equipment.
- Switch off the internal and external cache using the BIOS setup.
- Avoid overclocking of all kinds (CPU, system bus, graphics card)
- Reduce the bus clock (VLB maximum 40MHz,
PCI bus according to the specification, maximum
66 MHz ext. processor clock): use BIOS setup or jumpers on the
motherboard.
- Add waitstates: use BIOS setup
- Check if the BIOS option 15-16M Memory Hole is active. If
so, deactivate this option.
- Make sure the BIOS option PnP OS is set to 'No'. On some
systems, this option might be called Installed OS and should be
set to 'Other'. See "Problems caused by the BIOS option "PnP OS"" (http://sdb.suse.de/en/sdb/html/intnull.html).
- In (Advanced) Chipset Setup, if available,
set
CAS before RAS
: use BIOS setup
- Test the memory:
- To check your RAM, use memtest86 or follow the
instructions in "Checking system stability" (http://sdb.suse.de/en/sdb/html/hmeyer_memtest-sig11.html).
- There will always be problems where modules of different kinds are
used together.
- When using a PCI bus with 66 MHz, the DRAM modules
must
be specified with 60ns or less (no overtiming).
- Check the fittings of the RAM modules. They must fit exactly and must
not be loose or tilt. Remove the modules from the board and put
them back in
(check for corroded contacts).
- Change the order of the modules in the memory banks.
- Check if the CPU fan works 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 as a
source of errors,
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, optimize the kernel and the
programs for a 486 at the maximum. If might even be necessary to
fall back to 386 optimization.
- Check all general BIOS settings. If necessary, revert to the (rather
conservative) BIOS defaults.
- If the PC BIOS is buggy, the only solution is a
BIOS update.
Ask your local dealer or the manufacturer of the motherboard.
- The power supply does not provide enough electricity or the voltage
fluctuates: Try switching off some other appliances.
For More Information:
See also:
Checking system stability
Problems caused by the BIOS option "PnP OS"
SCSI-checklist
Adaptec 2940 - Reset Error
Keywords: HARDWARE, APM, 2940, INCONSISTENT DATA, INEXPLICABLE, SIG11, SIGNAL11, SEGMENTATION FAULT, POWER MANAGEMENT, MKFS, MKE2FS, CRC
Categories:
Frequently asked Questions
, Hardware
SDB-kfr_58, Copyright SuSE Linux AG, Nürnberg, Germany
- Version: 12. Mar 1998
SuSE Linux AG - Last generated: 15. Oct 2002 by sdb (sdb_gen 1.40.0)