Conclusions
A three-core processor is a little bit oddball, but I've made peace with the concept. For multitasking or more parallelizable workloads like image and video processing, choosing three lower speed execution cores over two higher performance ones might make some sense. This is a debatable proposition because desktop PC software has been annoyingly slow to migrate to multiple threads overall, but I see the potential merits. I can even see past the momentary road bumps we hit in programs like Windows Media Encoder, where only two cores were put to use. Those problems will be ironed out in due time.

The Phenom X3 processors' problems aren't in the concept, but the execution. The three cores simply aren't quick enough, individually, to make this triple-core product look appealing. They're a liability in single- and dual-threaded tasks, where the X3 8750 sometimes falls behind the much older Athlon 64 X2. The X3 8450 almost always does so. And the cores aren't quick enough to really sell the three-way concept when they are all working together. More than once, we saw the Core 2 Duo E8400 outperform the Phenom X3 8750 in intelligently multithreaded applications. Not only that, but the savings in peak power draw from deactivating a core weren't enough to put the Phenom into the same league as Intel's 45nm chips, which are astoundingly power efficient.

I can't help but think this all must have looked different on AMD's roadmap when it was first being put together. I doubt they expected that the fastest Phenom would only run at 2.4GHz and, in doing so, would only just match the Core 2 Quad Q6600—an older product on the way out, replaced by the Core 2 Quad Q9300. That's the reality, though, and it's constrained AMD's pricing so much that the top Phenom quad core is $235. The compression through the rest of the lineup makes the triple-core value proposition suspect. Give up a core to get 200MHz more at $195? Not likely when the Phenom X4 9850 Black Edition, at 2.5GHz with an unlocked multiplier, is 40 bucks more. The logic of the pricing scheme may be internally consistent, but the stakes are too low. I'd go with the X4 9850 ten times out of ten. If, that is, I were somehow bound and determined to choose an AMD processor over one of Intel's current offerings.