According to an Intel presentation about their upcoming LGA1155 "Sandy Bridge" CPUs, the company plans to intentionally limit the chip's overclocking capability; it appears that Intel only intends to permit a 2 – 3 percent overclock with the Base Clock adjustments.
BitTech states that “A video leaked to HKEPC and posted on YouTube (see from 2mins onwards) confirms the fact that only a 2-3 percent overclock via Base Clock adjustments will be possible. This is because Intel has tied the speed of every bus (USB, SATA, PCI, PCI-E, CPU cores, Uncore, memory etc) to a single internal clock generator issuing the basic 100MHz Base Clock.”
Image Credit: BitTech
The aforementioned clock generator is integrated with the P67 motherboard. It will transmit the clock signal to the CPU via the DMI (Desktop Management Interface) bus. The result being that there is no requirement to have an external clock generator. There are some tradeoffs for the lack of an external clock generator as well. In prior generations of chipsets, the external clock generator allowed separate overclocking of individual hardware. For example, the Memory clock, CPU clock, and SATA speeds have been individually adjustable on prior chipsets.
One Taiwanese company mentioned that an overclock of just 5 MHz on a Sandy Bridge system caused the USB and SATA ports to fail. Apparently, this new design was meant to cut production costs and make the board design simpler. Despite the downfalls of this approach, Intel’s Turbo Boost technology will still work. Turbo Boost is an intelligent self-overclocking feature of modern Intel CPUs. It will also still permit multiplier overhead for hardcore computer enthusiasts.
A further benefit of this chipset is that the memory strap limits are removed on current Sandy Bridge sample boards. However, it is not yet know if this capability will remain when Sandy Bridge motherboards are released.