Dell OptiPlex 990 (Early 2011) - Manual (Page 77)

Diskette subsystem reset failed
Description The floppy drive controller may be faulty.
Gate A20 failure
Description One or more memory modules may be faulty or improperly
seated. Reinstall the memory modules and, if necessary, replace
them.
General failure
Description The operating system is unable to carry out the command. This
message is usually followed by specific information—for
example, Printer out of paper. Take the appropriate action to
resolve the problem.
Hard-disk drive configuration error
Description The hard drive failed initialization.
Hard-disk drive controller failure
Description The hard drive failed initialization.
Hard-disk drive failure
Description The hard drive failed initialization.
Hard-disk drive read failure
Description The hard drive failed initialization.
Invalid configuration information-please run SETUP program
Description The computer configuration information does not match the
hardware configuration.
Invalid Memory configuration, please populate DIMM1
Description DIMM1 slot does not recognize a memory module. The module
should be re-seated or installed.
Keyboard failure
Description A cable or connector may be loose, or the keyboard or keyboard/
mouse controller may be faulty.
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