Obscure CPUs: Intel Xeon L5639 and X5679
Introduced in March 2010, Xeon 5600 family of server processors for dual-socket systems was refreshed in February of this year, bringing the total number of available models to more than 20. Specifications of these microprocessors are well known, and you can find them on our website or in the Intel ARK database. There are three Xeon 5600 CPUs that you won't find on Intel ARK site, though. One of them is a dual-core Xeon X5698, clocked at impressively high for x86 architecture 4.4 GHz. In March, we published a story about this CPU. Two other SKUs, virtually unknown to public, are L5639 and X5679.
Like all 5600-series Xeons, L5639 and X5679 are built on 32nm Nehalem microarchitecture. Both microprocessors pack 6 CPU cores with 256KB per-core L2 cache, and shared 12MB L3 cache, along with triple-channel DDR3 memory controller and QPI interface on a single die. Two Xeon models have HyperThreading technology enabled, and, as we suspect, support all advanced Nehalem features. The processors are produced in LGA1366 package, which requires socket 1366 motherboards.
Clocked at 2.13 GHz clock frequency, hexa-core Xeon L5639 fits right between 2GHz L5638 and 2.26GHz L5640 parts. The CPU has two QPI links running at 2.93 GHz. We believe the L5639 has 60W TDP, and at some point of time it was shipped in HP DL160 server. First information about this Xeon emerged in October - November of last year.
Xeon X5679 operates at 3.2 GHz, which is 133 MHz slower than X5680, and has 3.2 GHz QPI frequency. Unfortunately, we don't have CPUID for this chip, and we can't confirm individual core features. The only reliable information about this model is a processor picture (the picture is in the "Comments" tab), that was uploaded to our website two weeks ago.
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