Sun Microsystems Sun Blade 100, Service Manual

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Appendix C Functional Description C-17
C.6.2 DIMMs
C.6.2.1 Speed and Timing
The Sun Blade 100 uses PC100 compliant SDRAM DIMMs. The motherboard can
support up to 2 Gbytes with four DIMM slots. The CPU can address 2 Gbytes of
memory. The current maximum main memory is 512 Mbyte per slot. The DIMMs
comply with the following parameters:
C.6.3 SDRAM DIMM Configuration
The table below shows the different SDRAM DIMMs that can be used in the Sun
Blade 100 system.
SDRAM DIMM Modules implement the Serial Presence Detect (SPD) mechanism. A
serial EEPROM on the DIMM module contains data programmed by the DIMM
manufacturers that identifies the module type and various SDRAM organization and
timing parameters. This information can be accessed through the System
Management bus (I2C bus).
TABLE C-6
DIMMs Performance Range
Frequency Clocks tRC tRAS tRP
100Mhz (10ns) 4 70ns 50ns 20ns
TABLE C-7
SDRAM size options (DIMMs only)
DIMM
Mem Size
Configuration Technology
# of chips
on DIMM 2-DIMM
Mem Size 4-DIMM
Mem Size
128 Mbyte 16Mx72 128 Mbit 9 256 Mbyte 512 Mbyte
256 Mbyte 2 * 16Mx72 128 Mbit 18 512 Mbyte 1 Gbyte
512 Mbyte 2 * 32Mx72 256 Mbit 18 1 Gbyte 2 Gbyte