Intel Core I7 Review

Introduction:

About this time last year Intel launched what was the fastest 45nm quad core CPU on the planet, the Intel Core 2 Quad QX9770. Well, guess what, Intel has done it again with the latest architectural achievement, the Core I7 Extreme 965. What the two have is common is that they both are based on Penryn cores, they both are 45 nanometer chips and they both run at a clock speed of 3.2GHz. After these things what you have is a whole new animal. Gone from this chip is the twelve megabytes of L2 cache, this is replaced by a third level of cache at 8MB. Slow and inefficient it is not. With the addition of an integrated memory controller, the memory bandwidth is expected to be huge by comparison to today's top of the line processors, somewhere close to two to three times the peak bandwidth. SMT (Simultaneous Multi Threading) has made a return on the Core I7 generation. This will enable the processor to run a total of eight threads at one time. Some other new features are Dynamic Energy Management, new SSE4 instructions, three level cache with a shared 8MB L3 cache and improved branch prediction. Many are interested in the new efficiencies and features, while many think this generation will be the Holy Grail of processors, Let's find out just how it performs. That's the question that is on everyone's mind.

Closer Look:

When you look at the Nehalem CPUs by themselves you have to wonder what makes them so much different than the previous generation. On the left is the I7 965 Extreme Edition that features a non turbo multiplier of 24 and is unlocked both up and down. Couple the 24 multiplier with the 133MHz base clock frequency and you end up at 3.20GHz. The I7 920 is at the other end of the spectrum and has a maximum non turbo clock multiplier of 20 for a base clock speed of 2.66GHz, in turbo mode this will jump as high as 22 for a turbo speed of 2.93GHz, the same base frequency of the I7 940. To accommodate this massive chip the socket pin count is up to 1366 from the Core 2 processors 775 pin count.

In the pictures above the increase in the size of the die is not readily apparent. The die size on the Nehalem processor core has increased to 263mm2 with a total of 731 million transistors. Comparing the size of the I7 965 to a socket 775 processor makes the size increase that much more dramatic.

While both the I7 965 and i7 920 are engineering samples, the I7 920 was shipped with a retail heatsink. The size increase of the processor die necessitated a larger cooling solution as well. The same concept is used to cool the Nehalem chips that was used on the socket 775 processors, just larger. The copper center slug is surrounded by an aluminum fin matrix to shed the heat generated by the processor. Big is good when it comes to cooling!

Processor? Check! Motherboard? Check! It's time to see just what these little bits of silicon will be paired with to generate some performance numbers.