Review:
You have to sometimes wonder what's really going on at AMD.
AMD shipped its first 45nm quad core CPU, the Phenom II X4 model 940 Black Edition, along with model 920 in early January. Both were 45nm CPUs whose memory controllers only supported DDR2 memory. Since that original launch, prices have dropped, mostly in response to Intel price drops.
Note that the model 940 black edition clocked at 3.0GHz, while the model 920 ran at 2.8GHz. Each offered 512MB of L2 cache per core and 6MB of shared L3 cache.
So far, so good.
Now AMD is shipping its first socket AM3 CPU. The memory controller in socket AM3 CPUs is capable of supporting DDR3 memory. You would think that AMD would consider the launch of a CPU that finally supports the higher bandwidth of a newer memory type, DDR3, to be important enough to ship a flagship processor.
You would be wrong.
For its first set of socket AM3, DDR3-capable CPUs, AMD is shipping four cut-down Phenom II X4s and a pair of Phenom II X3s. The Phenom X4 model 810 and 805 CPUs only offer 4MB of L3 cache, down from the 6MB supported on the DDR2-only Phenom II X4 model 900 series. On the other hand, the Phenom II X3 model 720 Black Edition and model 710 have a full 6MB of L3 cache, but have one processor core disabled.
Confused yet?
Issues of product mix and confusion aside, it is interesting to see that AMD is finally shipping DDR3 capable AM3 CPUs, which are fully capable of also supporting DDR2. Our first round of benchmarks is only on a DDR2-capable motherboard, alas, because the one DDR3 board we had on hand turned out to be dead on arrival.
So let's see how the Phenom II X4 model 810 performs on a DDR2-capable socket AM2+ board.
The Phenom II X4 Model 810
Let's make one thing clear about all current Phenom II CPUs: The dies are identical. Whether it's the 3.0Ghz, DDR2-only model 940 Black Edition with its 6MB of L2 cache, the model 810, at 2.6GHz, with 4MB of L2 cache, or the Phenom II X3 model 720 Black edition with three cores and 6MB of L2 cache, the dies are the same. Different capabilities are enabled as warranted by yields and market realities. Let's take a look at AMD's entire 45nm product
At this point, the lowest cost, 45nm quad core Phenom II is the 810, at $175, which should be close to the retail price. The highest priced desktop CPU in AMD's line is the $225 Phenom II X4 940. At a die size of 258mm2 and 758M transistors, the margins aren't particularly hefty. But AMD can't really charge more, since the performance of the model 940 is roughly equivalent to Intel's Core 2 Quad Q9550, which can be found in the $275–$285 price range.
That leaves AMD at a serious disadvantage, since Intel offers at least three price and performance models above AMD's best—and those CPUs offer pretty serious margins for Intel.
AMD has been clever in offering the X3 models, which allows them to make use of dies where one core may not pass muster. That enables them to sell CPUs that otherwise might end up on the scrap heap. And now that AMD is getting out of the fab business, their cost structure is improving.
Still, without a true flagship part, AMD is left chasing after markets which Intel has previously ignored, like that for power-efficient CPUs. That window may also be fading, since Intel recently began shipping 65nm quad core CPUs: the Q8200s, Q9400s, and Q9550s.
From the user's perspective, however, that means you can pick up some pretty good bargains. The Phenom II X4 model 810 is priced a bit lower than Intel's Core 2 Quad Q8200, for example. On the other hand, the Q8200 gives up a 270MHz clock rate advantage against the X4 model 810. Given those thoughts, let's examine
The Benchmarks
We ran a number of performance tests that fell into three general categories: synthetic tests, such as 3DMark Vantage; applications-based benchmarks, like SYSmark 2007 or actual application tests; and game benchmarks. We expanded our series of tests, so we could get a good handle on the differences in performance between Intel's current and new generation quad-core CPUs.
