Installation guide

10 IBM Eserver xSeries 366 Technical Introduction
The XceL4v also functions as a snoop filter lookup table to reduce traffic on the front side bus.
Its embedded DRAM (eDRAM) stores a directory of all processor cache lines to minimize
snoop traffic on the dual front-side buses and minimize cache misses.
System memory
The models of the x366 have a 2 GB standard, implemented as two 1 GB PC2-3200 ECC
DDR2 DIMMs.
Memory is implemented in the x366 using memory cards. Each card has four DIMM sockets.
One memory card is standard and the x366 supports up to four memory cards. Using 4 GB
DIMMs in every socket (that is, a total of 16 DIMMs), the server can hold 64 GB of RAM.
The memory is two-way interleaved (meaning that memory DIMMs are installed in pairs). As
shown in Figure 3 on page 4, there are four ports to memory, with each supporting up to
5.33 GBps data transfers.
The DIMMs operate at 333 MHz (instead of 400 MHz as for the PC2-3200 spec) so that
throughput is 2.67 GBps (333 MHz x 8 bytes). At 2.67 GBps and two-way interleaving, the
throughput matches that of the front-side bus at 5.3 GBps so that bus transfers remain in
sync.
The x366 comes standard with one memory card and two 1 GB DIMMs. Memory is registered
ECC DDR2 memory meeting the PC2-3200 standard. Up to four memory cards are
supported, and each memory card can hold two or four DIMMs. (DIMMs must be installed in
matched pairs.)
By adding three additional memory cards (part number 13M7409) and using 4 GB DIMMs
(replacing the standard pair of 1 GB DIMMs), the x366 can be expanded to 64 GB.
Important: There must be at least one memory card with one matched pair of DIMMs
installed for the server to operate. Each memory card requires at least one matched pair of
DIMMs.