Intel quad-core Xeon 5300 review

Bensley platform

At first it will be possible to use the new quad-core Xeon DP processors on the same platform as the Xeon 5100 Woodcrest processors. The basis for the Bensley platform was introduced earlier this year in the form of the Intel 5000P (Blackford) chipset. The introduction of the Bensley platform meant a substantial improvement compared to the existing Xeon platform. The most important reason for this was the Dual Independent Bus architecture: with Bensley both processors are connected to the chipset with their own frontside bus. Intel increased the clock frequency to 1333 MHz and this equated into a vast increase of maximum data throughput between chipset and processor of up to 21 GB/s, whereas the previous platform with a single FSB had a maximum data throughput of 6.4 GB/s.

To ensure a comparably high memory bandwith for Bensley, Intel crossed over to FB-DIMM (Fully Buffered DIMM) modules. The Intel 5000P chipset has four memory channels so that, whilst using 667 MHz modules (FBD-667), a maximum memory bandwith of 21 GB/s can be attained. Thanks to the use of FB-DIMM it is now also possible to place up to 64 GB of memory into a single server. One drawback from using FB-DIMM technology is that the memory modules require a relatively large amount of electricity and because of this generate a fair amount of heat. A standard DDR2-module, such as AMD uses in its servers, uses around 4 Watt, whereas an FB-DIMM module uses in the region of 8 to 10 Watt. This has a definite impact on the total amount of power used by the server.

As Clovertown is compatible with the existing platform it means that it would be possible to upgrade a server using Xeon 5100 processors by replacing them with Xeon 5300 processors. In practice this wont be a likely scenario for most companies, unless the servers are running specialised HPC-applications where every percentage of performance gain is welcome. The greatest advantage of the Clovertown design is that every single large server manufacturer/supplier can offer servers based on the new quad-core processors in a relatively short space of time whilst keeping costs down.