AMD Phenom X3

Verdict: Produces more heat and is slower and more expensive than Athlon X2.

As their name suggests, Phenom X3 CPUs have three cores rather than the usual two or four. All three AM2+ Phenom X3s are based on the 65nm Toliman core and have a TDP of 95W. Cache configuration is identical to that of the Phenom X4-series, with 512KB of Level 2 cache per core and 2MB of shared Level 3 cache. We tested four Phenom X3 CPUs - the 8450, 8650, 8750 and 8750 Black Edition, which is an 8750 with an unlocked CPU multiplier.  

Despite having three cores, the benchmark results of the Phenom X3s were very poor. For example, the £56 Athlon X2 7750 Black Edition was faster in the Media Benchmarks; its score of 830 sneaked past the fastest Phenom X3 on test, the 8750 Black Edition, which scored 813 and costs £103. The £57 dual-core Intel Pentium E5200 also made a mockery of the triple-core Phenom X3s, with an overall score of 825. We overclocked the Phenom 8750 Black Edition from its stock 2.4GHz to 3GHz, which boosted its overall score to 949. However, this was only just ahead of the overclocked Athlon X2 7750 Black Edition, which scored 927.

The Athlon X2 7750 Black Edition proved its worth in Crysis too, achieving a minimum frame rate of 22fps. The Phenom X3 8750 Black Edition couldn't better this, also recording a minimum of 22fps. Power consumption is a weak point for the Phenom X3s too, with even the cheapest model, the Phenom X3 8450 causing the test PC to draw 190W - more than any Athlon X2 and the same as the Core 2 Quad Q6600, a much faster CPU.

The main reason for the Phenom X3s' poor performance is their low clock speeds. Given that the Phenom X3s are more expensive and run hot, none of these CPUs is worth buying. AMD's older Athlon X2s or the new Phenom II X3 720 Black Edition are much better value for money.