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Turn your dial to Socket FM1
Because we can never get enough code names, let's throw out a couple more. The mobile platform for Llano processors is code-named "Sabine," as you surely recall, and its desktop equivalent is named "Lynx." Lynx has, er, a few different spots than AMD's prior desktop platforms. Since Llano incorporates so many types of connectivity, a reworked CPU socket was unavoidable. Ladies and gentlemen, say hello to Socket FM1 and one of the first chips to drop into it, the A8-3850 APU:


The Socket FM1-based A8-3850 (left) and the Socket AM3-based Phenom II X4 840 (right)

We're a little surprised to see how much AMD went for physical continuity amidst the electrical change. FM1 remains a traditional socket, with the pins still protruding from the underside of the CPU package. Since virtually all of Intel's socketed products and AMD's own Opterons have made the transition to an LGA-style scheme where the pins sit on the motherboard, we half expected a change. Socket FM1 is even compatible with the same heatsinks and retention mechanisms used for other recent AMD sockets, from AM2 through AM3+. We had no trouble fitting an older tower cooler onto our A8-3850 APU. The FM1 pinout is clearly different though, with a total of 905 pins and a different gap arrangement, so the astute user shouldn't have any confusion about which chips fit into which sockets.

The non-astute user will still totally mash those pins, but that can't be helped.

Aside from the obvious physical differences, the desktop versions of Llano have a few other enhanced talents, including the ability to support higher DDR3 memory speeds of 1600 and 1866MHz. That capability is noteworthy because the higher-clocked IGP in those desktop APUs is almost certainly being held back at times by memory bandwidth limitations. Even so, we'd expect the vast majority of pre-built Llano desktops to ship with 1333MHz memory, at least initially.

For enthusiasts rolling their own PCs, though, the price difference between quality branded 1333MHz and 1600MHz DIMMs is almost nothing, so 1600MHz RAM could prove popular in that narrow window where folks care about graphics performance but not enough to purchase a discrete graphics card. (Both of those dudes will be really pumped about it.) On the other hand, 1866MHz memory still carries a substantial price premium—about $45 for a pair of 4GB DIMMs. That will change over time, though. The folks at Corsair tell us the spec for higher-speed DDR3 DRAMs has been approved by the JEDEC standards body, and DRAMs conforming to that spec are on the way. Once 1866MHz-capable DRAM chips are available in sufficient volume, that price premium should evaporate.

Of course, an all-new CPU platform requires all-new motherboards, like the one we used for testing, the Gigabyte A75M-UD2H, pictured above. The UD2H is a microATX board loaded with ports and connectors of all types.

AMD offers two "Fusion controller hub" south bridge chips for the Lynx platform, the A75 and the A55. Call me crazy suspicious, but I believe these are the exact same chips known as the A60M and A70M on the mobile side of the fence. The A75 is the pricier, higher-end model, distinguished by its support for two newer I/O standards, SATA 6Gbps and USB 3.0. Obviously, the Gigabyte board above is based on the A75M. A whole host of the usual suspects will be introducing Lynx-based motherboards, and we have a roundup of some of the first boards today.