Processors have evolved a great deal over the last few decades and there’s a lot to know and look for to make sure you get the right CPU for your needs. If you already have a motherboard, then make sure you choose a processor that can fit into the board you have. When building a system from scratch, you’ll want to consider all of your components together and pick a processor that will give you the speed and performance you want, and then choose a motherboard and other hardware to compliment it. While it may seem like there are a lot of numbers to understand about processors, once you know what to look for, it becomes easy to pick just the right CPU for your system.
Manufacturer
For mainstream processors, there are really only two manufacturers to consider: AMD and Intel. There’s a great deal of debate regarding which manufacturer is superior, but ultimately it will come down to what level of performance you want, your budget, and personal preference.
Intel vs. AMD
In general, AMD processors can be more affordable and offer excellent speed and performance with many cores in a single CPU. Intel processors are often more expensive, while offering excellent speed due to hyperthreading. Whichever manufacturer you ultimately choose, make sure you pick the same type of motherboard, as Intel CPUs can’t work in AMD motherboards, nor can AMD processors work in Intel boards.
Socket Type and Series
The socket type of a processor indicates what sort of motherboard it can fit into. AMD and Intel each have their own socket types, and several different ones are currently popular. A processor can typically only fit into a single type of socket, so it’s important you pick one that is compatible with your motherboard.
Intel sockets include LGA 1150 and LGA 2011, while popular AMD sockets include FM2, AM3, and AM3+. The series depends on the manufacturer and typically indicates the generation of a processor. For example, Intel indicates series numerically with i5 released before i7, and each series has different features. AMD uses other notations, however, such as FX-series and A-series, which refer to different types of processors. For the best performance possible, consider an Intel i7 or AMD FX-8 or FX-9 series CPU.
Core Name
Core names are often terms or internal codenames used to refer to different types of processor chips. Each new generation or significant improvement on a line of CPUs typically has a new name, and while you don’t always need to know these names when buying a processor, it can be helpful when reading reviews. Haswell is the most popular and current Intel chip name which you’re likely to see when looking at Intel i5 and i7 processors. Vishera is the most common, recent core name for AMD models. In general, you’re better off looking at CPU series, rather than codenames.
Number of Cores
Additional cores in a processor let a CPU basically act like multiple chips together on a single system. Increased performance is not purely multiplicative, so a dual-core CPU doesn’t exactly double the performance; however, it still provides better speeds than an older, single-core processor. Quad-core CPUs have become increasingly common and affordable, so consider a processor with at least four cores. If you really want incredible performance, you can find six-core and even eight-core processors offering amazing speeds when running multiple programs and demanding software.
Hyperthreading
When looking at Intel processors, you want to consider threads in addition to cores. Hyperthreading uses virtualization to effectively double the number of cores, but does so through non-physical means. Multiple cores are physical while multiple threads do not involve the presence of additional physical cores. A dual core CPU with hyperthreading basically acts like a four-core processor, while a quad-core processor with hyperthreading works like an eight-core CPU. If you pick an Intel processor, then you probably want to find one with multiple cores and hyperthreading, though AMD processors don’t use hyperthreading.
Frequency (Speed)
The frequency, measured in megahertz (MHz) or gigahertz (GHz), basically indicates the speed of a processor. The CPU in a computer acts as the beating heart of a system, the faster it beats, the faster all of the applications on that computer run. You’ll typically find processors listed with operating frequency and maximum frequency. The operating speed is how fast the CPU usually runs; while maximum frequency shows the top speed you can easily boost it up to, usually through boosting provided by the manufacturer.
You can overclock a processor to run even faster, which can take it far beyond the maximum speed listed by Intel or AMD, but make sure you know what you’re doing before overclocking a CPU. Try to get the fastest CPU you can afford, but don’t only focus on clock speed as multiple cores are just as important.
Cache Memory
Cache memory is a small amount of very fast memory used by a processor to retrieve data quickly and run programs as fast as possible. You’ll typically see modern processors with L2 and L3 cache memory. You want a processor with as much of this memory as possible, usually measured in megabytes (MB); however, this isn’t something you’ll need to spend a lot of time worrying about. If you find a CPU with a good number of cores and a fast clock speed, it’s very likely it will have a good amount of cache memory too.
Integrated Graphics
In the past, you would typically find integrated graphics on a motherboard and it was usually pretty unimpressive. More recently, manufacturers have added graphics processing onto CPUs. This is more common with AMD processors, but you can find it with Intel models as well. On AMD processors there are even models, usually A-series ones, which include multiple cores dedicated to graphics processing. If you’re not planning on spending extra on a dedicated graphics card, then a processor with cores for video processing can help improve your video performance. This is less important if you’re going to install one or more video cards, but keep it in mind as you’re looking at different models.
Cooling and Power Requirements
Although you can add your own heatsink and cooling to a processor after you install it, most CPUs come with a cooling option included. If you plan on running your processor at normal speeds and you don’t care about the most powerful performance possible, then a heatsink and fan should be sufficient for keeping your CPU cool.
Very powerful processors that are good for overclocking might include liquid cooling options that are much more efficient than air cooling. A lot of processors will run just fine with a baseline 350-400 Watt power supply, but some very powerful models might require better power supplies. For more information to help you pick the right PSU for your system, take a look at the power supply buyer’s guide.