IBM RS6000 - 7026 - H70 Service Manual

Also see for RS/6000 7025 F50 Series: User guide Service guide Service guide

Memory Test Hang ProblemGeneral Memory Information: Memory Card cards can be installed in eitherslot (or both) on the System Board, there is no requirement that one be installedbefore the other.It is perfectly acceptable for there to be 2 partially populated Memory Cards, the firstone does not have to be fully populated before memory on the 2nd Memory Card isusable.Memory Card memory DIMMs, on the other hand, must be installed in matched (sizeand speed) pairs. Refer to the “Removal and Replacement Procedures” for “MemoryModules” on page 6-26 for labeling of the Memory Card and instructions on moduleremoval and installation (do not, however, replace the covers as directed whiletroubleshooting this problem). A single memory DIMM pair may be installed inmodule slots 1 and 2 (not slots 1 and 3). A second memory DIMM pair could beinstalled in module slots 5 and 6 (slots 3 and 4 do not have to be populated first).Along these same lines, there is no requirement that memory DIMM slots 1 and 2 bepopulated before another slot pair.Problem resolution steps: This section attempts to trouble shoot a problemduring the memory testing where the system hangs before an error code can bedisplayed on the Operator Panel.1. Power down the system2. Remove and re-install any installed Memory Card(s), power the system up. Ifthe system no longer stops at an E3xx code, re-seating the Memory Card(s) hascorrected the problem.3. Attempt to isolate the problem to a specific Memory Card.a. If there is only 1 Memory Card installed, tag the card as suspect bad andskip to step 4 on page 3-43.b. Remove one of the 2 Memory Cards, tag the card as suspect bad and Powerthe system up. If the system no longer stops at an E3xx code, skip to step3d.c. Power down the system, remove the installed Memory Card and install theMemory Card removed in step 3b. Move the suspect bad tag from theinstalled Memory Card to the one just removed, and power the system up. Ifthe system stops at an E3xx code, remove the suspect bad tag and skip tostep 7 on page 3-44, if the system does not stop at an E3xx code, skip tostep 4 on page 3-43.d. Power down the system, remove the installed Memory Card and install theMemory Card removed in step 3b (tagged as suspect bad). Power thesystem up. If the system stops at an E3xx code again, skip to step 4 onpage 3-43.3-42 Service Guide