Core i3 vs. i5 vs. i7

Intel has been using the i3, i5, and i7 naming scheme for their CPUs for quite a while now, but what these labels mean tends to slowly change over time as new features are introduced or older ones get replaced. On top of this, the naming scheme between desktop and mobile CPUs is often different as well. In this article, we will go over what differentiates i3, i5, and i7 processors for both mobile and desktop Haswell CPUs.

The biggest thing you need to know in regards to the i3, i5, and i7 naming scheme is that it is primarily a way for Intel to separate their CPUs into three performance tiers:

Intel Core i7: High-end
Intel Core i5: Mainstream
Intel Core i3: Entry-level

There are a few differences in features (notably Hyperthreading, cache size, and number of cores), but as we will show later in this article there is actually very little that differentiates an i5 CPU from an i7 CPU. The biggest thing that this naming scheme gives you is a starting place when choosing a CPU. If you use your computer for basic tasks like surfing the web, then an i3 CPU is likely a great choice. If you use your computer for a variety of tasks that require a bit more power (including gaming), than an i5 CPU might be a better choice. If you run multiple applications that require a lot of CPU power, then an i7 CPU is probably right for you.Overall, the chart above can be summarized with the following:

The CPU frequency and thermal output (TDW) is largely not determined by the Core i_ name
Core i5 and i7 both have Turbo Boost while the i3 does not
Core i5 and i7 CPUs have 4 cores, while i3 CPUs only have 2
Core i5 CPUs lack Hyperthreading
Core i7 CPUs have more Smart Cache than i5 CPUs, which in turn have more cache than i3 CPUs
Core i5 and i7 CPUs have the same graphics, although the speed of that graphics will depend on the individual CPU. Core i3 CPUs have variable graphics depending on the price-point of the CPU.
So while i7 CPUs do have overall better specifications than i5 CPUs, there is actually quite a bit of overlap between the two except that i5 CPUs do not support Hyperthreading. Especially in terms of frequency and thermal output, the two lines really are not very different. For i3 CPUs, the main difference is that they only have two cores, a smaller cache, do not support Turbo Boost and have overall lower thermal output than i5 and i7 CPUs.