Acer Altos G520 Service Manual page 24

Memory Combinations
DIMM1B
256MB
512MB
1GB
2GB
256MB 256MB
512MB 512MB
1GB 1GB
2GB 2GB
256MB 256MB
512MB 512MB
1GB 1GB
2GB 2GB
NOTE: Altos G520 provides four DDR333 DIMM slots in dual memory channels. DIMM 1A and DIMM 2A
are connected to memory channel A. DIMM1B and DIMM2B are connected to memory channel B. The
maximum memory capacity is 8GB DDR333 memory. Memory DIMM technologies supported are:
256MB, 512MB, 1GB, and 2GB.
NOTE: 2-way memory interleave requires symmetrical memory modules using the same density (e.g. 256MB,
512MB), bus width (e.g.x8, x16) and granule technology (e.g. 256Mb, 512Mb).
Memory Sparing
DIMM 1B
256MB 256MB
512MB 512MB
1GB 1GB
2GB 2GB
TO provide a memory fault tolerant system, Altos G520 includes specialized hardware to support fail-over
to a spare DIMM device (DIMM 2B and DIMM 2A) in the event that a primary DIMM in use exceeds a specified
threshold of runtime errors. One of the DIMMs installed per channel will not be used, but kept in reserve. In the
event of significant failures in a particular DIMM, it and its correpsonding partner in the other channel (if
applicable), will over time have its data copied over to the spare DIMM(s) held in reserve. When all the data
has been copied, the reserve DIMM(s) will be put into service and the falling DIMM will be removed from
service. Only one sparing cycle is supported. If this feature is not enabled, then all DIMMs will be visible
in normal address speace.
16
DIMM1A DIMM2B
256MB
512MB
1GB
2GB
DIMM 1A DIMM 2B (Spare)
256MB
512MB
1GB
2GB
DIMM2A
1-way
1-way
1-way
1-way
2-way
2-way
2-way
2-way
256MB 2-way
512MB 2-way
1GB 2-way
2GB 2-way
DIMM 2A (Spare)
Physical Memory
256MB 1GB
512MB 2GB
1GB 4GB
2GB 8GB
Memory Interleave
Total Memory
Detected by OS
512MB
1GB
2GB
4GB
Chapter 1