Let's talk now about the new Intel E8500 chipset and its new features.

This chipset has the following basic specs:

• PCI Express bus support (three 8x slots and  one 4x slot).
• PCI-X bus support (one PCI-X 133 slot and two PCI-X 100 slots).
• Four memory channels, allowing a maximum theoretical transfer rate of 12,800 MB/s using DDR2-400 memories.
• DDR266, DDR333 and DDR2-400 memories support (pay attention because this chipset doesn't support DDR400 memories but DDR2-400).
• Supports dual-core Xeon CPUs (code-named Paxville).
• Two independent busses. At the previous chipset for Xeon MP (Intel E8870) all system processors shared the same 400 MHz (3.2 GB/s) bus. In this chipset we have two independent busses of 667 MHz (5.3 GB/s) each, thus it is said that servers based on this CPU has an external maximum theoretical transfer rate of 10.6 GB/s. If two processors are used, each processor will be installed on a separated bus. If a four-CPU configuration is used, each bus will have two CPUs installed.

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Figure 3: Intel E8500 chipset dual bus architecture.

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Figure 4: Intel E8500 chipset summary and comparison with a ServerWorks GC-HE chipset solution.