Intel Kaby Lake-X i7 7740X and i5 7640X : The New Champion

Intel Kaby Lake-X i7 7740X and i5 7640X : The New Champion for single threading:

Intel’s direction for the high-end desktop space has taken an interesting turn. After several years of iterative updates, slowly increasing core counts and increasing IPC, we have gotten used to being at least one generation of microarchitecture behind the mainstream consumer processor families.

There are many reasons for this, including enterprise requirements for long support platforms as well as enterprise update cycles. For 2017, Intel is steering the ship in a slightly different direction, and launching the latest microarchitecture on the HEDT platform. These CPUs don’t feature the high core counts of the other HEDT parts, but offer a higher point up the voltage/frequency scale to be the fastest single thread processors money can buy. They also overclock quite well.


(adsbygoogle = window.adsbygoogle || []).push({});

Detailing :

Users that have been in the enthusiast space will have realized that the Holy Grail for PC performance is single threaded (ST) performance. If you master single thread throughput, then arguably the rest is easier, such as scaling out to more cores. There are usually three barriers to high ST-perf: instructions per clock (IPC), frequency and power consumption.

A high IPC is fundamental to such a design, as any gains will propagate through the platform, but is becoming a tough job. Over the last few generations, Intel has increased IPC by 3-10% each generation, making a 30-45% increase since 2010 and Sandy Bridge depending on the benchmark, but we’re unlikely to see 50-100% jumps per generation any time soon. Any IPC gains are multiplied through the frequency at which the processor runs at, which can be limited by a combination of things: production process (e.g 14nm), voltage characteristics, stability, yield etc.

These features tie directly into power consumption, which increases as a square of voltage and with frequency/capacitance. With some designs, +10% frequency might be possible, but at the cost of +100% power, so there also needs to be a balance to have something marketable that people will want to buy.




(adsbygoogle = window.adsbygoogle || []).push({});

At the heart, the new KBL-X processors are no different to their mainstream platform KBL-S brethren. The silicon is the same, but potentially binned for a better voltage/frequency curve, and then packaged into the HEDT platform rather than the mainstream platform. Unlike the mainstream processor stack though, Intel is only launching two processors. A Core i7-7740X and a Core i5-7640X.Both CPUs are quad core, with the Core i7 having Hyperthreading for a total of eight threads.

The Core i5 does not have hyperthreading, making it the first HEDT processor in the modern Core era to do so. Both will have identical support to their KBL-S siblings, although the increased base/turbo frequencies have resulted in Intel’s TDP increasing from 95W to 112W. The TDP rating is a guide for appropriate cooling: the KBL-S processors were actually very good on their power consumption at stock frequencies, and as shown later, so are the KBL-X processors. Intel could have kept the 95W TDP rating very easily here.

%d bloggers like this: