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Combining
High-Speed Scalability Ports
When more than one chassis is used, they are simply cabled together via one or more scalability cables. Up to three cables connected to
This feature is another unique IBM enhancement, not offered by other x86 server architectures.
DDR II ECC Memory with Active Memory Protection
The eX4 servers support up to 256GB of memory per node (chassis) in 32 DIMM sockets (up to 1TB for a
The standard configuration includes two memory cards, which support up to eight DIMMs apiece. The system is upgradeable to four memory cards with eight DIMMs each. With configurations of
The memory architecture of the eX4 chipset provides up to 60% more aggregate memory bandwidth (up to 34.1GBps when using four memory cards vs. a maximum of 21.3GBps bandwidth in the previous generation), for exceptional memory performance, and quadruple the system memory capacity of the predecessor x3850 server. By performing reads and writes simultaneously, it eliminates the previous memory
Memory scrubbing is an automatic daily test of all system memory. It detects and reports memory errors that might be developing before they cause a server outage. Memory scrubbing and Memory ProteXion work together. When a bit error is detected, memory scrubbing determines whether the error is recoverable. If the error is recoverable Memory ProteXion technology will write the data to new location; if it is not recoverable, scrubbing sends an alert to light path diagnostics, which then notifies IBM Systems Director.
Memory ProteXion technology (also called redundant bit steering) provides multichip error protection and works in conjunction with Chipkill
Memory mirroring works much like disk mirroring. The total memory is divided into two channels. Data is written concurrently to both channels. If a DIMM fails in one of the DIMMs in the primary channel, it is instantly disabled and the mirrored (backup) memory in the other channel becomes active (primary) until the failing DIMM is replaced. Note: Mirroring requires DIMMs to be installed in multiples of four (one pair per memory channel).
A secondary benefit of memory mirroring is that the failed DIMM and its memory card can be
DIMMs must be installed in matching pairs. Memory is available in kits consisting of two 1GB, 2GB, 4GB or 8GB DIMMs.
Flexible Internal Storage Capacity
The eX4 servers offer a choice of internal storage, supporting up to four
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