Efficiency Comparison: Sandy Bridge Vs. Intel And AMD CPUs


Intel's new Sandy Bridge processor architecture and H67 platform are impressive both in terms of performance and power efficiency. Together, they easily outperform the competition in terms of performance per watt. That include the existing Core i3/i5/i7 lineup employing LGA 1156 and AMD's fastest Socket AM3 product portfolio.

We considered several AMD processor options for a broad efficiency comparison, but an apples-to-apples comparison is hard: not many AMD CPUs below a Phenom II X4 would be appropriate if you want to compare in a similar price corridor, and anything below the Phenom II X6 just isn’t capable of competing with Sandy Bridge.

It is important to understand that the Sandy Bridge architecture will fuel almost the entire Intel consumer portfolio in 2011, making this a critical product for the firm. Six- and eight-core processors will launch into the Xeon space later as well. Many people don’t like the fact that Intel is switching from the LGA 1156 to the LGA 1155 platform after only a year, but the significant changes in power consumption lead to massively varying currents. In the end, the voltage regulators have to be able to instantly, reliably, and durably switch from low to very high currents. In this light, the platform switch appears comprehensible and the fact that LGA 775 will be replaced by LGA 1155 in H2'11 underlines that this platform could be here to stay for a while.

What matters for consumers is that Sandy Bridge delivers at least four threads on Core i3 and four real, physical cores with Core i5 into the mainstream, at common price points and with top-notch features. Sure, AMD has been doing this aggressively as well. But with Sandy Bridge, we’re now looking at a performance level that can actually only be matched with six of AMD's Phenom II cores. At the same time, Sandy Bridge also matches the idle power consumption levels that so far were only reached by low-power processors or Atom-based systems. We’re talking about 30 W idle power paired with state-of-the-art quad-core performance.

If you don’t care for power consumption, then you will look at maximum performance per dollar, which remains important. There are great and, more importantly, much more affordable options in AMD’s portfolio. However, power consumption on Sandy Bridge is actually low enough to make even hardcore enthusiasts think twice. Isn’t it cool to have a machine capable running almost 5 GHz on air cooling that can actually switch off the CPU fan when the processor idles?

The good news for AMD is that there is still enough room to play the value card, especially since Intel severely limits the flexibility of its Core i3 CPUs. The truth is that performance is available in abundance for the majority of all users, and Intel basically confirmed this during a Sandy Bridge briefing when a journalist wanted to know when Intel would stop building dual-core processors. "We don’t see that." Hence, maximizing value by bringing power down and features up should help. There are opportunities to build in the future there with USB 3.0 and PCI Express 3.0.