Memory Ras Features; Table 9. Memory Ras Features - Dell PowerEdge M620 Technical Manual

DIMM DIMM
type 0
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SR
SR
SR
DR
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LRDIMM QR
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*Although the M620 supports DIMM speeds of 800MT/s and 1066MT/s, you can only purchase this system with DIMM
speeds of 1333MT/s, 1600MT/s and 1866MT/s on Dell.com/PowerEdge.

Memory RAS features

Reliability, availability and serviceability features help keep the system online and operational without
significant impact to performance, and can decrease data loss and crashing due to errors. RAS aids
in rapid, accurate diagnosis of faults which require service. Table 9 describes the memory RAS
features supported on the M620.
Feature
Dense configuration
optimized profile
Memory demand and
patrol scrubbing
Recovery from single
DRAM device failure
(SDDC)
Failed DIMM isolation
Memory mirroring:
intra-socket
Memory address parity
protection
21 PowerEdge M620 Technical Guide
DIMM DIMM Number
1 2 of DIMMs
DR
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Table 9. Memory RAS features
Description
Increased memory reliability can be a result from this selectable platform profile
that adjusts parameters to reduce faults regarding refresh rates, speed,
temperature and voltage.
Demand scrubbing is the ability to write corrected data back to the memory once
a correctable error is detected on a read transaction. Patrol scrubbing proactively
searches the system memory, repairing correctable errors.
Recovery from Single DRAM Device Failure (SDDC) provides error checking and
correction that protects against any single memory chip failure as well as multi-bit
errors from any portion of a single memory chip.
This feature provides the ability to identify a specific failing DIMM channel pair,
thereby enabling the user to replace only the failed DIMM pair.
Memory mirroring is a method of keeping a duplicate (secondary or mirrored)
copy of the contents of memory as a redundant backup for use if the primary
memory fails. The mirrored copy of the memory is stored in memory of the same
processor socket.
This feature provides the ability to detect transient errors on the address lines of
the DDR channel.
800* 1066*
2 ∞ ∞
2 ∞ ∞
3 ∞ ∞
3 ∞ ∞
3 ∞ ∞
3 ∞ ∞
1 ∞
2 ∞
3 ∞
Speed (MT/s)
1333 1600
∞
∞
∞
∞
∞ ∞
∞ ∞
∞
1866
∞