First the good news. The AMD Phenom II X2 550 beats the opposition where it matters most. In our World of Conflict game benchmark it keeps its eyes on the prize and edges the Athlon II X4 620, Athlon II X3 435 and the Phenom II X3 720.
In fact, it's usefully faster than the two Athlon chips clocking up 33 frames per second compared to 35 and 37 frames per second, respectively. The triple-core Phenom II X3 720 gets a little closer at 42 frame per second. But part one of the Phenom II X2 550 BE's job is done. Its advantage in gaming gets even bigger when you take overclocking into account. 4GHz on air cooling is clearly quicker than its closest competition and allows the 550 pulls further ahead.
That said, if you're willing to spend a more on an Intel chip, you'll get way more gaming performance. The Intel Core i5 750, for instance, delivers 59 frames per second despite its modest 2.66GHz clockspeed. Make no mistake, running at its maximum 4.2GHz overclock, the Intel chip absolutely annihilates the Phenom II X2 550 BE in games.
As for all round system performance, the dual-core 550 is inevitably rather weak. It simply cannot keep up with processors with double the number of cores, such as the Athlon II X4 620. We're also disappointed to find that our 550 sample fails to function when you enable the two hidden cores. So much for the idea of getting a quad-core chip on the cheap.
If building a gaming rig on a very tight budget is your bag, the dual-core AMD Phenom II X2 550 Black Edition just about adds up. It's definitely a more effective gaming chip than other low-cost AMD processors. It also overclocks pretty well.
The 550 might be faster than other cheapo chips. But it's still a lot slower in games than a decent Intel processor. Likewise, it struggles with any software that thrives on multi-core processor architectures. It would also be unwise to assume that the 550's two hidden cores are likely to work when unlocked.
Just about makes sense for gamers on a tight budget. Not a great all rounder.
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