Another Clash Of The $100 Dual-Core Titans
The AMD Phenom II X2 555 and Intel Pentium G6950 are dual-core CPUs that cost about $100 retail. That's where the similarities end.
Intel's 2.8 GHz Pentium G6950 is the lowest-end model available for the LGA 1156 platform. This processor is essentially a Core i3-series processor stripped of Intel's Hyper-Threading feature. The Pentium also has less L3 cache memory than the Core i3 models, sporting 3MB instead of 4MB. This CPU represents Intel's starting point for an LGA 1156 system, something an entry-level customer can whet his or her feet with, while allowing attractive upgrade options to Core i3, i5, and i7 LGA 1156-based CPUs.
Although it'd seem to be a notable disadvantage, Intel's Pentium G6950 makes the fully-modern Clarkdale design available at a reasonable price point, and it centers on a very overclocking-friendly 32 nm manufacturing process. We'll see if this is enough to challenge AMD's $100 dual-core contender.
| Header Cell - Column 0 | Phenom II X2 555 | Pentium G6950 |
|---|---|---|
| Codename: | Callisto | Clarkdale |
| Process: | 45 nm | 32 nm |
| CPU Cores: | 2 | 2 |
| Clock Speed: | 3.2 GHz | 2.8 GHz |
| Socket: | AM2+/AM3 | LGA 1156 |
| L1 Cache: | 2 x 128KB | 2 x 64KB |
| L2 Cache: | 2 x 512KB | 2 x 256KB |
| L3 Cache: | 6MB | 3MB |
| Thermal Envelope: | 80W | 73W |
That counterpoint is the Phenom II X2 555 Black Edition, AMD's quickest dual-core CPU. It sports 6MB of shared L3 cache, twice that of the Pentium G6950. This is the fastest dual-core CPU AMD has ever released, and with a 3.2 GHz stock clock speed, it's 400 MHz faster than the stock Pentium G6950. The Phenom II X2 555 also comes with an unlocked CPU multiplier, as indicated by its Black Edition designation, and that means that the CPU can be simpler to overclock for enthusiasts who prefer multiplier-based tuning. Finally, since these processors are really quad-core CPUs with two of the cores shut off, some folks have been able to turn on those dormant CPU cores. This means that the dual-core Phenom II X2 555 CPU has the potential to operate with four CPU cores, like the more expensive Phenom II X4 955.
On the downside, the Phenom II X2 555 is built on older 45 nm manufacturing technology and won't typically overclock as high as the new Intel models. As far as unlocking the dormant CPU cores goes, this is not a guaranteed proposition. In fact, our experience has shown that fewer than 50% of samples can be unlocked with a capable motherboard. Most of the Phenom II X2 555 CPUs in the wild were originally intended to be sold as Phenom II X4 models, but failed quad-core suitability testing at the factory. If a single core on the processor die is flawed, the CPU is not thrown away, but “binned” as a candidate for a lower-end model like the Phenom II X2.
The question is, does the Phenom II X2 555 have enough strengths to surpass the Pentium G6950 at both stock and overclocked speeds? Or, will the new Clarkdale architecture and 32 nm manufacturing technology allow Intel's Pentium G6950 to show an advantage over the Phenom II X2?
Let's find out. First, a little overclocking is in order.
