Table 10-1 Valid Memory Configurations - Sun Microsystems Netra T4 AC100 Service And System Reference Manual

TABLE 10-1
Total Configured
Memory Density
3.0 GByte
4.0 GByte
4.5 GByte
5.0 GByte
6.0 GByte
8.0 GByte
10.2.2.3 Interleaving
The main memory supports interleaving on 64-byte boundaries. The memory system
supports from one to four logical banks. The DIMMs support two banks. For
interleaving purposes, all banks are treated identically regardless of their physical
location. Two successive accesses to distinct logical banks located in the same group
of DIMMs are processed the same as accesses to logical banks that are in separate
groups of DIMMs.
The memory controller for the Netra T4 system supports 2-way and 4-way
interleaving.
The main memory is accessed only on 64-byte block reads or writes. The interleaving
is based on a 64-byte addressing and the four low-order bits of a block physical
address (PA[9:6]) determine the bank within a memory segment. The stride on
which banks are interleaved is 64 bytes (no interleaving), 128 bytes (2-way
interleaving), 256 bytes (4-way interleaving).
In only one configuration is it possible to interleave by four. Both groups must be
populated with DIMMs of the same size supporting two banks.
10.2.2.4 Memory Timing
The CPU module memory controller is programmable so that different SDRAM
speeds can be accommodated at different system clock frequencies and different
processor clock ratios. The memory bus timing is controlled by a set of four memory
timing control registers.
10-10 Netra T4 AC100/DC100 Service and System Reference Manual • August 2001
Valid Memory Configurations (Continued)
Even Bank 0 DIMMs
512 MByte
256 MByte
512 Mbyte
1 GByte
empty
1 GByte
128 MByte
1 GByte
256 MByte
1 GByte
512 MByte
1 GByte
Odd Bank 1 DIMMs Interleaving
256 MByte 2-way
512 MByte 2-way
512 MByte 2-way/4-way
empty 2-way
1 GByte 2-way
128 MByte 2-way
1 GByte 2-way
256 MByte 2-way
1 GByte 2-way
512 MByte 2-way
1 GByte 2-way
1 GByte 2-way/4-way