Apple Xserve G5 Computer Accessories User Manual


 
Support for up to 8GB of RAM
Xserve G5 comes standard with 512MB or 1GB of DDR SDRAM. Main memory is scalable
up to 8GB in eight DIMM slots, allowing you to increase memory as application and
networking requirements increase. More main memory enables the system to run
strenuous processes simultaneously and to accommodate spikes in demand. Enormous
files and data sets can be loaded into RAM for rapid processing by the PowerPC G5—
without having to access disk storage. Data is transferred to memory 40 times faster
than to the hard drive. In fact, accessing the first critical word of data from memory is
60,000 times faster than from a hard drive, so manipulation and analysis of data can be
performed at remarkable speeds.
ECC protection
Xserve G5 uses Error Correction Code (ECC) logic to protect the system from data
corruption and transmission errors. Each DIMM has an extra memory module that
stores checksum data for every transaction. The system controller uses this ECC data
to identify single-bit errors and corrects them on the fly, preventing unplanned system
shutdowns and protecting data integrity. In the rare event of multiple-bit errors, the
system controller detects the error and triggers a system notification to prevent bad
data from corrupting further operations.
For additional protection, the ECC modules on the DIMMs integrate with Server Monitor
software. If error rates exceed a defined threshold, which typically indicates a hardware
problem, Server Monitor can alert the administrator for fast resolution.
High-Performance PCI-X Expansion
Xserve G5 features the latest 133MHz PCI-X expansion protocol with throughput of up
to 1GB/s. PCI-X operates more efficiently than PCI, resulting in more usable bandwidth
at any PCI-X bus speed—ideal for connecting to high-performance networking, storage,
and backup devices using optional SCSI and Fibre Channel cards. For fast data access,
the PCI-X bus connects to the system controller using a high-speed, dual-channel
HyperTransport bus with a throughput of up to 4.8GB/s (2.4GB/s each way).
Two open 64-bit PCI-X slots allow you to add one card running at up to 133MHz
or two cards running at up to 100MHz. The PCI-X specification is designed to support
3.3V signaling and is compatible with Universal 33MHz and 66MHz PCI cards.
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Dual Onboard Gigabit Ethernet
Apple extends the networking performance of Xserve G5 with a high-performance
Ethernet controller on the main logic board. This advanced controller includes two
independent 10/100/1000BASE-T Ethernet interfaces, each with its own interrupt, on a
dedicated 64-bit, 133MHz PCI-X bus. The result is tremendous networking bandwidth
and no contention for data with the I/O subsystems.
In addition, the Gigabit Ethernet controller provides these networking features:
Hardware-generated TCP, IP, and UDP checksum detects packet corruption and
transmission errors.
802.1q VLAN (Virtual LAN) tags allow Xserve G5 to be a member of multiple virtual
networks and to provide unique network services to each one.
A large 64K packet buffer per interface supports jumbo frames, or packets up to 9K,
to reduce system overhead and increase throughput of all network activities.
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Technology Overview
Xserve G5
PCI expansion options
Built-to-order Xserve G5 configurations can
include the following:
Apple Fibre Channel PCI Card
Hardware RAID PCI card
Apple PCI-X Gigabit Ethernet Card
Dual-channel Ultra320 SCSI PCI-X card
VGA video card