Memory Modules; Memory Module Population Rules - Sun Microsystems Sun Fire V20z User Manual

4.5.11

Memory Modules

The Sun Fire V40z server contains memory modules in four memory-bank locations.
Two banks are on the motherboard and two banks are on the optional CPU card. Use
the correct procedure in this section:
"Replacing a Memory Module on the Motherboard" on page 4-51
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"Replacing a Memory Module on the CPU Card" on page 4-52
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4.5.11.1

Memory Module Population Rules

Use the following information and rules when you use the procedures in this section
to replace or add dual inline memory modules (DIMMs) to the server.
DIMMs used in the server must all be of the same type: "Registered DDR 333" or
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"Registered DDR 400".
Caution – The Registered DDR 400 memory DIMMS can only be used in the
updated release (chassis PN 380-1206) of the Sun Fire V40z server.
If you are installing the new Registered DDR 400 memory DIMMs in your server,
you must also install the new 2.6V voltage-regulator module (VRM) (PN 370-7747).
Note – If you mix two different types of DIMM, the memory clocks down to the
lower speed. Sun Microsystems, Inc. does not support this configuration.
Note – A maximum of 6 GB of memory per CPU is currently supported in the Sun
Fire V20z server at DDR 400 speed: two 2-GB DIMMs and two 1-GB DIMMS. In this
case, you must insert the 2-GB DIMMs in the bank next to the CPU and the 1-GB
DIMMs in the outer bank.
If more than 6 GB of DDR 400 memory is installed per CPU (meaning, 2-GB DIMMs
in all four memory slots), the system will access at the memory only at DDR 333
speed.
Four DIMMs are supported per CPU. The four DIMM slots for each CPU are
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grouped into two banks (bank 0 and bank 1) that contain two slots each.
The Sun Fire V40z server supports either two- or four-CPU configurations. Each
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CPU can use two or four DIMMs; when using only two DIMMs for a CPU,
populate the bank closest to the CPU first (bank 0) .
DIMMs must be installed in matched pairs (one bank at a time). The two DIMMs
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in a bank must be of the same size, type and vendor.
Chapter 4 Maintaining the Sun Fire V40z Server 4-49