IBM H Series Installation And Service Manual page 172

a. Power the system down. Removing the currently installed memory module
first, re-install one of the two suspect bad memory modules in its original
position.
b. Power the system up. If the system again stops at an E3xx code, the
memory module tagged suspect bad just installed is defective, replace it with
the memory module removed in step 5a. If the system did not stop at an
E3xx code, remove the suspect bad tag from the memory module just
installed - it is not defective.
6. Replace the memory card
7. Replace the system board.
8. Replace the CPU card(s).
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RS/6000 Enterprise Server Model H Series Installation and Service Guide