Intel Sandy Bridge Previewed

Anandtech has published an in-depth preview of Intel's upcoming Sandy Bridge CPUs. The Roadmap has been confirmed as the one previously leaked,and just as confusing, alongwith pricing indications. However, perhapsthe most important question would be - How fast is Sandy Bridge? The CPUAnandtech tested was a 3.1 GHz quad-core sample, the same speed as theCore i5 2400. Unlike the eventual i5 2400, however, the sample couldhave HyperThreading enabled but Turbo disabled. Clock-for-clock, SandyBridge is approximately 10% faster than Lynnfield, and perhaps a fewmore percent with Turbo enabled. This well supports long termspeculation that Sandy Bridge will only bring minor performanceimprovements, favouring efficiency.

Since Intel skipped quad-core for the Westmere 32nm refresh, today's Lynnfield CPUs are still 45nm. Hence, by moving to 32nm, Intel have been able to bump up the Sandy Bridge clock speeds significantly. Hence, the Core i5 2400 clocks in at 3.1 GHz, well over the 2.8 GHz Core i5 760. Thus, the Core i5 2400 will end up outperforming the Core i5 760 by around 25%, despite a lower price tag. It will consume less power as well. The real replacement for the i5 760, and possibly the best value-for-money part, will be the Core i5 2500K. This will be a 3.3 GHz CPU with no HT, but a Turbo Boost of 3.7 GHz. We can see this CPU comfortably outpacing the Core i5 760 by over 30%, at the same price point - $210. The most important part is the "K" suffix, indicating an unlocked multiplier. One of the major changes with Sandy Bridge is moving the BCLK generator to the chipset. Hence, this results in very limited overclocking of any kind from traditional means of increasing BCLK. The unlocked multiplier thus offers the best avenue for overclocking. The Core i5 2500 is identical to the 2500K, except it features a locked multiplier. The price difference between the two is $15 - something any overclocker can easily justify. If you are not interested in overclocking, the Core i5 2500 provides a formidable option at $196.

Above the Core i5 2500 series lies the only CPUs with HyperThreading for the initial release. Core i7 2600 is a 3.4 GHz product with 8 threads and 3.8 GHz turbo. However, unlike the Core i5 2500, the price difference between the locked and unlocked multiplier versions is massive. The i5 2500 is expected to be priced somewhere between $200 and $350 segment (more likely on the higher side), with the i5 2500K being priced as high as $562. At the lower end, the cheapest Sandy Bridge at release would be the dual-core Core i5 2100, which is a dual-core CPU clocked at 3.1 GHz, but with no Turbo. HT is enabled thankfully, for 4 threads. Lower priced Pentium branded products will release in Q2 2011 with even cheaper Celerons in Q3 2011.

The TDP for most quad cores will be 95W, with dual cores at 65W. However, the roadmap is further convoluted by "S" suffixed products, with TDP of 65W for quad-cores, and further low-power "T" products with 35W TDP for dual-cores and 45W TDP for quad-cores.

Finally, there is the on-die IGP featured with all Sandy Bridge products. While Intel made a major leap forward with Clarkdale, the graphics improvements with Sandy Bridge is even more impressive. Depending on the model, the IGP is clocked at 850 MHz, with an incredible 1350 MHz Turbo capability. The results are incredible, with Sandy Bridge obliterating not just Clarkdale, but every IGP out there today. In fact, it keeps up with the HD 5450 in most cases, and even sneaks by in some benchmarks. Low-res, low IQ gaming in modern games is definitely a possibility with Sandy Bridge for casual gamers.

Overall, there are no major surprises, and Sandy Bridge is turning out to be a worthy successor to the Nehalem generation. While it is an evolution of Nehalem rather than a brand new architecture, and clock-for-clock improvements are limited at best, Sandy Bridge makes up in the efficiency and clock speed department. Overall, we expect a roughly 30% increase in performance across the board at similar price points, with a drop in power consumption as well. Certain disappointments such as the very limited locked multiplier overclocking have been covered by unlocked K series CPUs and other benefits like AVX and massively improved graphics performance.

The Sandy Bridge CPUs previewed today by Anandtech will be available in January 2011. The lower priced CPUs will follow in Q2/Q3 2011. On the opposite end, the high-end LGA 2011 Sandy Bridge 6/8 core CPUs will only release in Q3 2011. With Sandy Bridge previewed and anticipated, the focus now shifts over to AMD's Llano.

For the full preview, you can read the Anandtech article.