Important Guidelines For Dimm Installation - Compaq PW5100 Reference Manual

8-4 Memory Upgrades

Important Guidelines for DIMM Installation

When installing DIMMs, you MUST follow these guidelines:
Use only 16-, 32-, 64-, 128-, or 256-MB, ECC, EDO-buffered DIMMs.
DIMMs should be 60-ns. The workstation will support DIMMs with a
speed of 50-ns, however, it is recommended that only 60-ns DIMMs are
installed. Since the memory timing registers can support only one
configuration, the entire memory subsystem will operate at a 60-ns
speed.
DIMMs must have a 4-KHz refresh rate.
DO NOT INSTALL DIMMS THAT DO NOT SUPPORT ERROR
CHECKING AND CORRECTING (ECC). Use only 3.3 volt, ECC,
EDO-buffered DIMMs. Non-compatible DIMMs may adversely affect
data integrity.
A DIMM can be installed one way only. Be sure to match the two key
slots on the DIMM with the tab on the DIMM slot. Push the DIMM
down into the DIMM slot, ensuring that it is fully inserted and properly
seated.
When upgrading, do not exceed 512 MB total. Upgrades exceeding
512 MB will cause the system to halt.
DIMMs must be added in pairs and each DIMM in a pair must be the
same size.
DO NOT INSTALL ANY ONE PAIR OF DIMMS IN ADJACENT
DIMM SLOTS.
Better performance can be achieved by alternating the installed DIMM
pairs between DIMM slots 1-4 and 5-8. In doing so, both memory
controllers are utilized by the system.
NOTE: If you must replace a DIMM module to upgrade your memory, see
"Removing DIMM Modules" later in this chapter for instructions.
IMPORTANT: The system will NOT boot if you install DIMMs in adjacent
slots. DIMMs must be installed in alternating (every other) DIMM slots.