IBM xSeries 380, Руководство по техническому обслуживанию аппаратной части

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Hardware Maintenance Manual: xSeries 380
This test finds soft errors in memory that are normally hidden by the cache memory
algorithms. This test defeats the caching strategy and accesses system memory
directly. This test also finds cache loading problems.
Address test
This test checks for shorts and opens on address lines. The address lines are used to
access data at a specified memory location. Data can be written to or read from the
wrong memory location if there is a short or malfunction in the address lines because
of a hardware problem. If the data is a part of the program being executed, the
program itself may malfunction. Select Memory from the Main Menu and Address
Test. Press <Enter> to start the Address Test. This test writes a value in one memory
locations and scans the entire range of system memory to find the value.
Refresh test
The type of memory used in almost all computer system memory is called DRAM
(Dynamic Random Access Memory). DRAM uses a small electric charge to store
memory. This charge must be refreshed approximately every 15.625 microseconds.
Certain programs detect the memory refresh interval and use the refresh rate for delay
loops. This AMIDiag test checks the DRAM system memory refresh interval rate.
When to Use Run the Refresh Test if a program that uses timing loops based on the
memory refresh rate does not work properly in your system. Many BIOS routines use
such timing loops, specifically routines that access the disk drives. Select Memory
from the Main Menu and Refresh Test. Press <Enter> to start the Refresh Test. If an
error occurs in this test, AMIDiag displays the current refresh rate and the ideal
refresh rate.
Data bus test
This test makes sure that the data bus is working properly. Choose Data Bus test from
the Memory menu and press <Enter> to run this test.
Cache memory test
This test identifies and tests all internal and secondary cache memory and then
performs a random pattern test within the range of the cache memory size to detect
cache memory problems. This test does not run if cache memory is not installed or is
disabled. This test always display the exact cache memory size.