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AMD has finally named its next-generation desktop processors; and the new name is Phenom. At the top of the product lineup we have the Phenom FX processors. These processors will be quad-core only and run at the highest clock speeds in AMD's lineup. Phenom FX processors will be available in both Socket-1207 and Socket-AM2 flavors. The X4 and X2 will be Socket-AM2/AM2+ only and are 100% backwards compatible with current AM2 motherboards.

Phenom will work in current Socket-AM2/Socket-1207 motherboards with a BIOS update, but it loses the ability to run its Northbridge and CPU cores at separate voltages/clock frequencies. If you buy a new Socket-AM2+/Socket-1207+ motherboard, then the CPU cores and Northbridge can run at separate voltages/frequencies. The benefit of doing this is not only power savings, but AMD has indicated that it can actually run the Northbridge faster than the CPU cores (by 200 - 400MHz) which will improve performance. The L3 cache happens to run on the same voltage plane and at the same frequency as the Northbridge, compounding the performance benefits of using a new "plus-socket" motherboard (Socket-AM2+/Socket-1207+).

Given that Phenom will be DDR2 from the start, it looks like AMD's transition to DDR3 will be much like its transition to DDR2: it will complete well after Intel has made the move. AMD's current roadmap shows the second generation Phenom core (Shanghai) due out in 2008 but still on Socket-AM2+/1207+. It's quite possible that AMD will introduce another socket in late 2008 (AM3?) that will offer DDR3 support to begin its transition to the new memory technology.

Izvor: AnandTech