Which CPU Should You Buy? Intel Core i5 vs. i7

For many consumers on the hunt for a new desktop or laptop PC, one of the biggest considerations is the type of processor the system should have. Two of the CPU families most often in contention in mainstream systems are the Intel Core i5 and the Intel Core i7. And that makes picking tricky, because the two lines have a lot in common.

The differences among Intel's key processor families are clearer when you're looking at the Core i3 (found mainly in budget systems) or the Core i9 (powerful CPUs for content-creation and other high-performance scenarios). The differences between the Core i5 and the Core i7 can seem subtle and more nuanced, especially when the prices for a Core i5 versus a Core i7 PC sometimes can be so close.

There isn't always a clear-cut, definitive answer to which is better in a given situation, and often, it just comes down to your budget. But knowing the essentials about each can help you make a smarter choice. Let's get into the key differences between the Core i5 and the Core i7.

How Many Cores Is Enough?

Simply put, a Core i5-equipped system will be less expensive than a Core i7-equipped PC, if all else is equal. But in most cases, if you're comparing apples to apples (that is, a desktop chip to a desktop chip, or a laptop chip to a laptop chip, and the same generation to the same generation), the Core i5 will have fewer, or dialed-down, capabilities. A Core i7 will typically be better for multitasking, media-editing and media-creation tasks, high-end gaming, and similar demanding workloads. Often, though, the price difference will be small, so it's worth playing around with the online configurator of whatever PC you're buying to see if you can afford a Core i7-powered machine.

When you're using software that can leverage as many cores as it can get (modern content-creation programs, like the ones in the Adobe Creative Suite, are excellent examples), the more cores you have in your CPU, the faster it will perform.

Most of the latest Intel Core i5 and Core i7 CPUs have four or more cores, which is what we consider the sweet spot for most mainstream users. Many late-model desktop Core i5 and Core i7 chips have six cores, and a few ultra-high-end gaming PCs come with eight-core Core i7s. Meanwhile, a few ultra-low-power laptop Core i5 and Core i7 CPUs have just two. You'll find these mainly in ultra-thin laptops.

The same rough Core nomenclature has been used for quite a few generations of Intel CPUs now. To make sure you're buying a system with a recent-generation processor, look for the Core ix-11xxx or Core ix-10xxx naming structure. Some CPUs designed for thin or mainstream laptops have a "U" or a "Y" appended to the end of the model name, while others have a "G" followed by a number that denotes the capabilities of the chip's graphics processing. Chips meant for power laptops tend to end in "H" or "HK"; and those intended for desktops have a "K" or a "T" at the end (or just end in a zero).

Unless you're shopping the used-PC market, you'll find Core i5 and i7 chips of the 8th and 9th Generation (or older) in end-of-life/closeout systems and some budget PCs, while you'll find 10th and 11th Generation chips in most new models. The rough guide, if you don't want to get in too deep: To get better performance within each generation and within each class (Core i5 or Core i7), buy a processor with a higher model number. For instance, an Intel Core i7-1060G7 generally has better performance than an Intel Core i7-1065G7.

A Quick Word on Cache

In addition to generally faster base clock speeds, Core i7 processors have larger amounts of cache (the memory installed on the chip) to help the processor deal with repetitive tasks or frequently accessed data more quickly. If you're editing and calculating spreadsheets, your CPU shouldn't have to reload the framework where the numbers sit. This info will sit in the cache, so when you change a number, the calculations are almost instantaneous. Larger cache sizes help with multitasking, as well, since background tasks will be ready for when you switch focus to another window.

Cache size isn't a make-or-break spec, but it illustrates advances from generation to generation and family to family. The latest Core i5 and Core i7 laptop processors have cache sizes of 16MB or less.

Turbo Boost and HyperThreading

Turbo Boost is an overclocking feature that Intel has built into its processors for many generations now. Essentially, it allows some of the chip's cores to run faster than their base clock speed when only one or two of the cores are needed (like when you're running a single-threaded task that you want done now). Both Core i5 and Core i7 processors use Turbo Boost, with Core i7 processors generally achieving higher clock speeds.

Each chip you're looking at will have rated base and boost clock speeds, and while higher is generally better (again: all else being equal), it depends on the specific design and cooling of the PC how long a chip can sustain its boost speeds, how high, and on how many cores. That's where looking at nitty-gritty performance testing comes in.

Intel Hyper-Threading, in contrast, is a has-it or doesn't-have-it feature. It uses multithreading technology to make the operating system and applications think that a processor has more cores than it actually does. Hyper-Threading technology is used to increase performance on multithreaded tasks, letting each core address two processing threads at the same time instead of just one. The simplest multithreaded situation is a user running several programs simultaneously, but other activities can leverage Hyper-Threading under certain conditions, such as media creation and editing work (notably, transcoding and rendering, where the software supports multithreading) and even at times web surfing (loading different page elements, like videos and images, simultaneously).

In general, all else being equal, a CPU that supports Hyper-Threading in a given family will be more capable than one that does not, if what you do day to day is heavily influenced by this feature. This is even true between Core families, which means that it may be better, if your software relies heavily on multithreading, to choose a four-core chip with Hyper-Threading over an equivalent six-core without.

When shopping for PCs, alas, it's not always easy to find information on the number of cores, or the presence or absence of Hyper-Threading support, on a PC vendor's spec list. If you can find the chip's exact model number, though, plug it into Intel's specs database, which will show you clock speed, core count, Hyper-Threading support, and much more.

Understanding Integrated Graphics

Most thin and light laptops with Core i5 or Core i7 processors that aren't gaming machines rely on integrated graphics-acceleration silicon that's part of the CPU die. Gaming machines and certain high-end systems, on the other hand, have dedicated graphics chips that are separate from the CPU.

Core i5 and Core i7 chips come with different kinds of integrated graphics capabilities. At the low end are Intel HD Graphics and Intel UHD Graphics. Iris Plus is a step up, available on many 10th-generation chips. The latest and greatest integrated graphics is Iris Xe, available on only a few 11th-generation Core i5 and Core i7 models.

Integrated graphics save power, since there's no extra graphics chip on your laptop's or desktop's motherboard drawing juice. Intel's integrated graphics solutions work well for mainstream productivity and display (including multidisplay) tasks. Both Iris Plus and Iris Xe can rival the capabilities of a low-end discrete GPU like Nvidia's GeForce MX series.

Integrated graphics are not so great at handling demanding PC games, though. While these integrated Intel graphics processors will let you play some recent games at low quality and resolution settings (how well varies significantly by the game), you will definitely need a discrete graphics card from AMD or Nvidia to play 3D games at 1080p, 1440p, or 4K resolutions with the quality settings turned up. Nor are integrated solutions the best choice for tasks that demand GPU acceleration in addition to CPU muscle, such as certain specialized, heavy rendering and scientific applications.

Core Outliers: Core X-Series and Core Y Mobile

Intel's Core X-Series desktop processor family, introduced in 2017, is aimed at high-performance users like extreme gamers and video editors. The Core i7-7820X processor, for example, has eight cores and, thanks to its Hyper-Threading support, can process 16 threads simultaneously. Most of these chips retail for well over $500 (some as high as $2,000!) and are overkill for most casual or even mainstream users who perform tasks like productivity work and web surfing, or even most serious PC gamers. These CPUs are positioned as high-performance hardware for 3D rendering, mathematical calculations on large data sets, 4K video processing, game development, and to an extent high-end gaming (with multiple video cards).

Unless you fall into one of the above buckets, you can safely ignore the Core i5 (now end of life, and not recommended) and Core i7 X-Series CPUs and opt for an ordinary desktop Core CPU instead. There is no equivalent to the Core X-Series for laptops.

At the distant other end of the spectrum are Intel's Core Y-series processors for laptops. They are aimed at extremely thin-and-light ultraportable laptops. In recent generations, these chips, such as the Core i7-10510Y, consume just 7 watts of power and generate very little heat, which can eliminate the need for a cooling fan.

Making the Core Choice

In our testing in recent years, we've seen a few trends to keep in mind when you're deciding between processor options. On the desktop, Intel's Core i5 caters to mainstream and value-minded users who care about performance, while the Core i7 is made for enthusiasts and high-end users. On the laptop side of things, it's a little fuzzier; there, you'll want to look more at whether Hyper-Threading is supported by a given chip and how many cores the chip has, as well as how a chip performs in independent testing in a given laptop configuration. How the laptop maker implements a chip and cools it can be just as important as the CPU's spec traits.

That's solid advice for mainstream buyers. Beyond that, only extreme users need to consider Intel's desktop Core X-Series, and only people for whom a laptop's weight and portability matters above all else need to consider the Y-Series.

Posted in: Hardware