Apple Xserve G5 High-Performance PCI-X Expansion, Dual Onboard Gigabit Ethernet, ECC protection

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

Technology Overview 15

Xserve G5

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.6

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.