Intel’s Xeon E3-1200-Series Family

Eleven new processors populate the Xeon E3-1200 series. Five are server-specific, four are workstation-specific, and two are low-voltage models that won’t be sold at retail (they’re tray-only). Architecturally, all 11 chips are very similar. They center on the same Sandy Bridge design introduced on the desktop earlier this year.

That means they’re manufactured on a 32 nm process, employ up to four execution cores, and include as much as 8 MB of last-level cache. Hyper-Threading and Turbo Boost are enabled or disabled on a per-model basis, serving as differentiators. The same dual-channel memory controller is there, accommodating up to 32 GB of DDR3-1333. And there’s also an integrated PCI Express controller, plus the logic corresponding to Intel’s HD Graphics 3000 engine.

There are some notable differences between the desktop Core family and these new Xeons, though. To begin, the memory controller supports ECC-capable modules. That’s not even worth a footnote on a desktop platform, but it’s an important addition to servers and workstations tasked with money-making jobs. “Yeah, yeah, yeah,” you say. “I use desktop hardware at work all of the time and it’s just fine.” And so do I. But I also have more than a handful of painful memories when a story I was writing disappeared after a random blue-screen. Those are the situations ECC memory is intended to help prevent.

The Xeons also have more PCI Express connectivity. That’s right—here we all thought Sandy Bridge was limited to 16 lanes and three controllers. In fact, the Xeon implementation offers 20 lanes and four controllers. Sixteen makes sense on the desktop, where enthusiasts are most likely to monopolize them with a single GPU or split them with a pair of graphics cards. In the server space, however, you have 10 Gb Ethernet controllers, SAS cards, and Fibre Channel HBAs using x8 and x4 slots. An additional four lanes of PCIe come in useful.

Finally, there’s the issue of integrated graphics. Intel uses the same die across its Xeon E3 lineup. However, its retail server parts see that engine disabled entirely. One of its low-voltage offerings includes HD Graphics 2000. And the workstation SKUs come armed with HD Graphics P3000, which we’ll cover shortly.

As you can see, there’s more choice in the Xeon E3 family than Intel’s second-gen Core i7, i5, and i3 lineups combined. And aside from one low-voltage tray model, they all include at least four physical cores. They’re also predominantly armed with Hyper-Threading and equipped with a full 8 MB of L3.

All but one of the retail server-oriented models sports an 80 W TDP, indicative of the tighter constraints on 1U rack-mounted machines. The workstation-class processors employ the same 95 W rating as Intel’s desktop processors. And the low-voltage parts are available at 45 and 20 W TDPs.

Up and down the lineup you see some of the same capabilities already discussed on the desktop: Turbo Boost, Demand-Based Switching (similar to SpeedStep), and AES-NI support. FlexMigration is a cool capability that the Xeons uniquely get, though, that allows them to operate in a virtualized environment alongside other, older virtualized servers. Generally, the risk there would be migrating a VM from one system to another (based on a dissimilar architecture), without the same virtualization acceleration features. FlexMigration basically recognizes each generation of hardware in your infrastructure and uses the lowest common denominator, preventing a compatibility clash. Of course, it’s not ideal to disable new features, but when it’s the difference between throwing away usable servers to avoid crashes, well…