Dell Latitude CP Reference And Troubleshooting Manual

Also see for Latitude CP: Service manual Service manual

Contents

Running the Dell Diagnostics 4-13Why Run a RAM Test?Faulty memory can cause a variety of problems that maynot, at first glance, appear to be happening in RAM. If thecomputer is displaying one or more of the followingsymptoms, run both the subtests in the RAM test group toverify that the memory is not at fault:• A program is not running as usual, or a proven pieceof software appears to malfunction and you confirmthat the software itself is not at fault. (You can con-firm that the software is functioning properly bymoving it to another computer and running it there.)• The computer periodically locks up (becomes un-usable and must be rebooted), especially at differentplaces and times in different programs.SubtestsThree subtests are available for the RAM test group: theQuick Test, the Comprehensive Test, and the SecondaryCache Test. The Quick Test performs an address check todetermine whether the computer is properly setting andclearing individual bits in RAM, and whether the RAMread and write operations are affecting more than onememory address location at a time. This subtest checksall available RAM, including the secondary cache. TheComprehensive Test also performs an address check, aswell as the following:• Data pattern checks, to look for RAM bits that arestuck high or low, short-circuited data lines, andsome data pattern problems that are internal to thememory chips• A parity check that verifies the ability of the memorysubsystem to detect errors• A refresh check, to verify that the dynamic RAM(DRAM) is being recharged properlySystem Set Test GroupThe subtests in the System Set test group check the com-puter’s basic system board components and verify theirrelated functions.Why Run a System Set Test?The System Set subtests double-check many systemboard components, such as the computer’s I/O circuitry, thatare tested by other test groups or subtests in the diagnostics.You should run the System Set test group if you are having aTable 4-3. RAM Test SwitchesSwitch Description–r number Repeats the subtest this number of times. Valid numbers are 1 through 9999. A value of 0 causes thetest to run until you press . The default value is 1.–m number Stops the test if this number of errors occur. Valid numbers are 1 through 9999. A value of 0 causesthe test to accept an unlimited number of errors. The default value is 0.–s hexadecimalmemory addressStarts the test at this hexadecimal address. Valid hexadecimal values are 0 up to the highest memoryaddress. The default value is 0.–e hexadecimalmemory addressStops the test at this hexadecimal address. Valid hexadecimal values are 0 up to the highest memoryaddress. The default is the highest memory address.–o[f filename,p] Outputs the test report to a file (f) or a printer (p). If you output to a file, append the filename afterthe f parameter. If you do not specify a filename when using the f parameter, the test report is outputto a file named result. If you output to the printer, the test file is output to LPT1.–[q,c] Runs the quick (q) or comprehensive (c) subtest. The comprehensive subtest is the default value.–np Does not pause when an error occurs or a subtest finishes. Pause (p) is the default value.