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Intel's Sandy Bridge - the Next Gen

Intel's Sandy Bridge - the Next Gen



The 6-series Chipsets and a Short FAQ

The Intel P67 Express 

Designed for those who are pairing their Sandy Bridge processor with a discrete graphics solution, Intel's P67 Express chipset is targeted at the performance mainstream crowd. It's also the only option for consumers that require multi-GPU support, with CrossFire/SLI supported thanks to its two PCIe 2.0 x8 lanes. On paper, it's an incremental upgrade from the previous P55 Express chipset, with the main difference being the presence of SATA 6Gbps support on the P67. Best of all, the eight PCIe 2.0 lanes from the chipset is rated at a full 5Gb/s bandwidth, a big leap from the 500Mb/s on the 5-series. This should provide sufficient bandwidth for other onboard controllers and devices, from more SATA 6Gbps controllers to USB 3.0.

Speaking of which, the sole disappointing aspect is that USB 3.0 is still not found natively on the chipset, though motherboard vendors have softened the impact by including USB 3.0 controllers on practically all new 6-series motherboards.

The Intel H67 Express

Like the Intel H55/H57 Express, the new H67 Express comes with support for the integrated graphics capability on all Sandy Bridge processors. This means that on a H67 motherboard, you're likely to find display outputs like HDMI and DisplayPort. From what we have seen, four options, VGA, DVI, HDMI  and DisplayPort appear to be fairly common from board manufacturers. These outputs will make use of the single PCIe 2.0 graphics (16 lanes) from the Sandy Bridge processor. 

Besides this, the rest of the H67 is identical to the P67. Overclockers should take note that the chipset limits CPU overclocking. While the graphics and memory clocks can be increased, we found no such options for the CPU on the H67, even with a 'K' processor. Basically, there's no point getting a 'K' processor with a H67 board.

 

A Couple of Sandy Bridge Questions...

During the course of our testing, we naturally had some questions about the new processors for Intel. Here are our questions and the replies from Ramaprasad Srinivasan, Platform Marketing Manager, Intel Asia Pacific

Are there any specific architectural changes that warranted a new socket for these processors? We would like a sound explanation on what caused Intel to create yet another socket change.

Sandy Bridge and Clarkdale desktop processors are not pin compatible. Both use a 37.5 mm x 37.5 mm LGA package but they are not electrically or mechanically compatible. This is due to architectural changes over the prior generation. In Core 2010, we had a MCP (Multi chip package – CPU on 32nm, graphics on 45nm). In 2nd Gen Core, we take integration to the next level with graphics built in on the die (monolithic all 32nm).

This is an architectural change, the pin outs are different. Now supposing, even if we were to have the same socket, it would not mean a thing as the current boards would not be able to support SNB using 5 series chipset, as you would need a 6 series chipset to support. So, seeing it that way, same socket or not, they would still need new boards with 6 series.

We realize that the bus speed has gone from 133MHz to just 100MHz. And that overclocking this bus is now very limited in range - about a 10MHz or thereabout? Could we find out what has brought about this change and why is it so limited?

For the desktop CPUs, Intel has traditionally limited the use of ratio-based overclocking to Extreme Edition parts and recently on the processors with the "K" suffix. Intel will continue to focus on the Enthusiast market segment providing more features to that audience. Allowing some degree of overclocking on other non-Extreme Edition or "K" SKUs is a strategy Intel is taking to further address these customers. We are excited about the opportunity this provides to the overclocking market. Intel determined the ratio limits to ensure a clear distinction from processors that are fully unlocked in order to create a collection of processors for the Enthusiast market based on the variety of overclocking needs in that segment.

Has Intel changed its stand in allowing overclocking on its processors?

Sandy Bridge represents an amazing feat of architectural innovation with a completely new level of integration and consolidation at the architectural level. This is Intel's first product where the graphics core is on-die. This level of integration increased the level architectural complexity. In order to meet other key design goals with respect to performance and power, design tradeoffs were made that resulted in reducing the range that BCLK can operate effectively relative to previous platforms. Intel ensures that the platform tools exist and function for those that decide to operate beyond Intel’s validated and warranted configuration.