There are many Intel processors available for purchase. These are grouped into a number of categories. The Intel Xeon processors are designed for use in workstations and servers, while the Intel Core and Pentium processors are for consumer applications. Just because an Intel Xeon is built for servers and workstations doesn’t mean that some performance obsessed gamers don’t build their gaming PCs around them. Likewise there are many servers and workstations that make do with an Intel Core processor.
Within the Intel Core range of processors, there are three distinct families: the Core i7, the Core i5 and the Core i3 families of processors. Within each of those families there are several processors with varying CPU clock rates and prices. To make things even more complicated, you could always buy a processor based on the previous architecture, in this case, Haswell or Broadwell.
So there are three main processor types to choose from when you’re building your custom gaming PC: the Intel Core i7, i5 and i3. How do you choose amongst them? Obviously the Intel Core i7 is the top-of-the line processor, provides the most performance and is also the most expensive. Many newcomers to PC gaming would simply choose the i7 but that isn’t always the right answer, particularly if it limits your budget for a graphics card.
What’s the difference between the Intel Core i5 vs Core i7? You might think it’s the number of cores, but for the most part desktop Core i5 processors have four cores, just like i7s. Intel Core i7 processors generally have faster base clock speeds, or in other words they have more Ghz. Within the i5 and the i7 families, there are individual processors with a four digit model number, like the Core i7-6700 and the Core i5-6600K. A higher number means better performance, as the i5-6500 is faster than the i5-6400. Remember how we said the Core i7 is generally faster than the i5? This isn’t always true, as the Intel Core i56600K is faster than the Core i7-6700, however it has less cache.
Cache is another major difference between the i7 vs i5. Core i7 processors have more cache, or onboard memory, to help them deal with repetitive tasks. This helps them save time by storing info in the cache instead of waiting to store and retrieve it from the memory on the motherboard. The Skylake Core i7 processors have 8 MB of cache while the i5s only have 6 MB.
The largest difference between the i5 and i7 is Hyper-Threading, which is a technology to increase the performance of multithreaded tasks. Hyper-Threading makes the processor appear to have double the cores to the operating system and applications. This is incredibly useful for multitasking, or tasks like video rendering or converting. All i7 processors have Hyper-Threading so four core processor can handle eight threads. A few i5 and i3 processors have Hyper-Threading, but they are limited to 4 threads total – either four real cores, or two cores Hyper-Threaded to handle four threads.
The final question is do you really need an Intel Core i7 or can you make do with and i5? It depends on what you’re going to be doing with your computer. For one, i7s are more expensive, and this can limit which graphics cards and other components you can buy. If you’re going to be doing a lot of video editing and/or you’re going to be streaming your gameplay on Twitch or YouTube, the Hyper-Threading abilities of an i7 could be worth it.
For most PC gamers however, an i5 is the better choice. Most games don’t make use of the Hyper-Threading technology, so there’s no point to it. Also, for most games an i5 will not bottleneck your gaming performance. Simply put, with an Intel Core i5 and an Nvidia GTX 980Ti, the processor will not be the component that holds back your frame rate. For more information, see our post on identifying bottlenecks in your gaming PC. An i5 will not bottleneck your gaming performance even if you’ve got two GTX 980s running in SLI! If you’re running multiple GTX Titan’s or three 980Tis then you should consider an i7 processor, but at that point budget doesn’t sound like a limiting factor. Overall when you’re building a custom gaming computer, your best bet would be to go with an Intel Core i5 and the best graphics card you can afford, instead of an i7 and getting a less expensive graphics card.