Our creative director Aurich Lawson is building a PC to power a custom arcade cabinet, and he was having trouble picking a processor. Not because he didn’t know what he needed, but because he was having trouble matching what he needed (the cheapest quad-core CPU that meets the recommended requirements for Street Fighter V) with what Intel was offering (five different obfuscated brands spread out over multiple sockets and architectures).

And if you’re building a PC now after having been out of the game for a few years, it can be exceptionally confusing. Around the turn of the millennium you just had Celeron and Pentium. One name meant “cut-down low-end” and one meant “high-end, more features,” and you just bought the fastest one you could reasonably afford. Things got a little more confusing in the Core and Core 2 days (the Core branding continues to survive alongside the Celeron and Pentium brands), but you could at least use names like “Core Solo” and “Core 2 Quad” to guess which architecture and how many cores you were getting. Now there are three separate Core brands, Pentium and Celeron brands, and a long series of letters that you need to know to figure out what CPU you’re getting.

It's been a few years since the last time we demystified Intel’s CPU lineup, and in truth things haven’t changed too much. In broad strokes, the rules are the same. But Intel has introduced and retired a few CPU architectures and brands since then. We’ll run down the basics for both desktops and laptops to help you make some sense of things whether you’re building a computer or buying one from someone else.

First: Know your architectures

Right this second we’re in a sort of transitional phase where some old CPUs are still filtering out as new ones filter in. In brief:

The old chips, codenamed Haswell, are generally identifiable by their 4000-series model numbers or the “4th generation Core” label. The desktop chips use socket 1150 motherboards. In general, we would recommend against considering these for new builds or purchases unless you can get a really good deal—Haswell is at the end of its life and Intel won’t be making new chips for its socket in the future. There are also a handful of 5000-series, 5th-generation Broadwell desktop chips that use the same socket—Intel didn't do a full release of these CPUs because of manufacturing delays, so you'll find the majority of them in laptops instead.

The new chips, codenamed Skylake, have 6000-series model numbers and a “6th generation Core” label. The desktop chips use socket 1151 motherboards, which is likely (not guaranteed, but likely) to see additional use in the upcoming Kaby Lake and Cannonlake architectures later this year and into next year. If you care at all about future-proofing, the small price premium is worth paying if you're building a desktop.

Desktops: Celeron, Pentium, and Core

There are a total of five separate processor brands that all share the Skylake architecture and the socket. I’ll list the high-level differences of each along with exceptions, and then we’ll get into model number suffixes.

Celerons and Pentiums

Both of these are budget brand names, and processors in both lines tend to be differentiated by clock speed and not much else. Skylake Pentiums are G4000-series chips, while Celerons are G3000-series. They’re all dual-core CPUs with no Turbo Boost, no Hyperthreading, and 3MB of cache, and they’re typically paired with the basic Intel HD 510 integrated GPU.

Core i3 CPUs are a little faster, but Pentiums will give most price-conscious people the best bang for their buck.

Exceptions: The Pentium G4500-series chips get an Intel HD 530 GPU that’s quite a bit faster than the 510 (within the realm of integrated graphics, anyway).

Core i3

These CPUs are still dual-core but add Hyperthreading, which presents two logical processor cores to the operating system for every physical core. This can definitely help performance in multithreaded workloads, though it’s nowhere near the boost you’d get from moving to a quad-core CPU. Core i3-6100 CPUs include 3MB of cache while 6300-series chips include 4MB of cache; nearly all of them use the Intel HD 530 GPU.

Exceptions: The Core i3-6098P uses an Intel HD 510 GPU.

Core i5

These are all quad-core CPUs without Hyperthreading, and they probably represent the best balance of price and performance for high-end users. They also use Intel’s Turbo Boost feature, which let the CPU run at higher clock speeds when there’s enough thermal headroom or when fewer cores are being actively used.

Not all workloads will benefit from two extra processor cores, but video editing, Photoshop work, and an increasingly large number of games are all happier with four cores. All of these CPUs include 6MB of cache and most of them have Intel HD 530 GPUs.

Exceptions: The Core i5-6402P includes an Intel HD 510 GPU.

Core i7

These are best described as Core i5 chips with Hyperthreading, higher clock speeds, and and 8MB of cache. Otherwise they’re the same. As with Core i3 CPUs, Hyperthreading definitely does help performance in heavily threaded programs, but jumping from a Pentium or Core i3 to a Core i5 will get you a much larger performance bump than jumping from an i5 to an i7.

Exceptions: None. There aren’t many of these processors yet.

Desktop Processor suffixes

The Celeron, Pentium, and various Core labels tell you most of what you need to know about a given CPU, but the model number suffix is important too. Here’s what these suffixes mean (and note that some CPUs have more than one letter attached).

No suffix: These are “mainstream” CPUs with no particularly special properties.

T-series: These are low-power desktop chips with lower TDP values, which generally (but not always) translates into lower power consumption. These power savings are usually realized by reducing the CPUs’ maximum clock speed. For example, a Core i7-6700 has a TDP of 65W, a base frequency of 3.4GHz, and a Turbo frequency of 4.0GHz. A Core i7-6700T has a TDP of 35W, a base frequency of 2.8GHz, and a max clock speed of 3.6GHz.

K-series: This relatively rare suffix denotes a multiplier-unlocked CPU that can be overclocked when paired with a high-end Intel Z170 chipset. The chips also have a higher 91W TDP, relative to the standard 65W for a quad-core CPU.

E-series: E is for “embedded,” which implies that these are mostly going to come with pre-built systems or soldered to motherboards. System builders can mostly ignore this one.

P-series: Back in the Core 2 days, a P-series chipset didn’t include an integrated GPU. Now, P-series chips just include slower integrated GPUs. Go figure.