April 23, 2009

As was increasingly expected, AMD has officially updated its Phenom II processor line with two new, slightly faster CPUs. The unlocked 3.2 GHz Phenom II X4 955 Black Edition (about $245) supports over clocking and is the company's fastest yet, while the Phenom II X4 945 (about $225) is clock-locked at 3 GHz. AMD says the former flagship 3 GHz AM2+ Phenom II X4 940 BE (about $195) will "remain available as an over lockable Black Edition for a period of time."

The new chips again feature a total cache (L2+L3) of 8MB, and though geared for use with Socket AM3/DDR3-memory motherboards, are also backwards-compatible with AM2+/DDR2-memory systems; so the good news is that you needn't upgrade your entire PC to use them.

Though AMD has trailed Intel in CPU performance at the absolute top end of town, it's continued to deliver an affordable and largely competitive computing platform that includes CPU, motherboard, and GPU. The current incarnation of this unified offering is dubbed Dragon, and the new CPUs top off a full refresh since its introduction at CES in January. New ATI Radeon HD 4890 graphics boards hit earlier this month, Socket AM3 motherboards are rolling out, and AMD's long-awaited OverDrive 3.0 overclocking software is expected to make its appearance at today's launch, albeit in beta form.

My tests of the pre-release OverDrive 3.0 software revealed a veritable tweaker's paradise. You can tweak processor, HyperTransport, and memory speed and voltages with unmatched granularity, or simply move a slider in novice mode. Phenom II chips may not be able to catch top-flight Core i7s in performance, but AMD knows that when it comes to enthusiasts sometimes it's not how fast you go, but how much fun you have getting there.

AMD touts the overclocking abilities of the Black Edition Phenom IIs and indeed, the CPU can be cranked well beyond its stock clock speed. In my personal hands-on I managed 3.6GHz using only the rather tame stock cooling solution provided by AMD. The company claims speeds up to 3.8GHz are safe, though it points out that the chip's warranty doesn't cover damage caused by overclocking. On the extreme side of things, hobbyists with early access to the X4 955 chip have apparently clocked it up to 6.5GHz. Intel's Core i7 965 Extreme Edition is also highly overclockable, but both it and the socket 1366 motherboards it runs on are far more expensive than AM3 products.