As we mentioned in our initial review of the Intel Core i7 Nehalem platform, the 920 and 940 run with different speeds than the 965 – beyond just the clock speed. The actual memory clocks run at different speeds, such as the QPI (QuickPath Interface, which replaces the FSB), L3 cache, and even the speed of the DDR3 memory being used.
The 965 normally has a QPI frequency of 6.4 GT/s, with the memory interface running at 1600 MHz. The 940 and 920 are meant to run with a 4.8 GT/s QPI and 1066 MHz memory interface.
We were told by Intel that these were all locked, and there would be no way to change this, without raising the 133 MHz base clock, which as we know, can significantly impact stability.
Naturally, all our Core i7 CPU’s are engineering samples from Intel, which are completely locked. But people are now discovering that their retail Core i7s have completely unlocked QPI and memory interface speeds.
So as long as you have a decent motherboard that can manually set these speeds, you can enjoy the same snappy QPI and full speed DDR3. Yup, the Core i7 already kicked ass, but now it’s even better than we thought.