How To Build A PC: From Component Selection To Installation

Step 2: Select Your CPU

Processor selection can be summed up in three words: performance, power, and price. Our Best Gaming CPUs For The Money column includes general performance and pricing data that applies to both gamers and non-gamers alike, and additional performance data is found in our CPU Performance Charts. It’s also important to know that when our gaming gurus recommend an overclockable “unlocked” processor, the non-overclockable version may offer the same standard-speed performance for less money. Overclocking is a group of techniques designed to push a part’s frequency beyond its designed operational parameters (voltage, heat, etc).

Those same CPU charts show idle and peak power draw, and specific power draw under various types of applications can be garnered through thorough reading of our CPU reviews.

Today, enough software relies on multi-core processing that AMD and Intel have all but eliminated single-core products from their product portfolios. Single-threaded workloads are still fairly common at the consumer level, and technologies like Turbo Boost (from Intel) and Turbo Core (from AMD) are designed to accelerate CPUs when they encounter those lighter tasks. As you read through our processor reviews, the Apple iTunes workload we run is a good example of a single-threaded test.

It’s certainly nice to know that modern operating systems can spread the load of multiple tasks over several cores, and that software developers can break certain tasks into jobs that multi-core processors can handle concurrently. But you're still wondering how many cores you need. If some are good, are more better? 

Not necessarily. Software isn't optimized to run across an infinite number of execution cores, and the more resources you duplicate on-die, the more complex your processor becomes, drawing more power. As with all things, there's a balance to strike, depending on what you use your PC for. If you're browsing the Web, responding to email, and writing in Word, most modern dual-core CPUs will feel plenty-lively. But once you start transcoding videos for your tablet or editing pictures taken on your DSLR, it gets a lot easier to overwhelm mainstream hardware.

Game developers have been trying to take advantage of multi-core processing for several years, yet we’ve rarely experienced a significant performance increase from having more than four cores. That’s probably why the largest manufacturer of desktop CPUs, Intel, focuses its gaming-oriented message primarily on four-core processors with the latest advancements in per-core and per-clock productivity.

Unable to match its chief rival in per-clock performance, AMD first countered by releasing processors with more cores for less money. The extra resources can come in useful in heavily-threaded tasks, but a big bump in clock frequency was the only thing that could keep AMD's older technology competitive in gaming circles. That came in late 2013 with two factory-overclocked models.

Power consumption is a major concern in environments where acoustics have to be kept in check. Typically, as you increase power, cooling requirements go up too. And that often means faster-spinning fans, which make more noise. The latest generation of low-energy Intel and AMD processors makes great strides in performance per watt used. Intel also offers even more miserly S-series variations of its Core i7 and Core i5 CPUs that can reduce heat inside high-performance machines.

Once you have a general concept of your own performance and power needs, the above-referred CPU Performance Charts, reviews, and Buyers Guide should help you narrow down a list of specific models you’d like to try. Of course, if you need a little extra guidance, check out Tom's Hardware's CPU forums, where you can ask questions and get answers.

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  • AndrewJacksonZA
    "the power supply is actually one of the more important parts of a build"
    Thank you!!

    Or rather, let's do what the cool kids are doing and rather post a GIF:
    https://giphy.com/gifs/the-office-thank-you-michael-scott-1Z02vuppxP1Pa
  • Eggz
    Great piece for a lot of first-time builders. This should have a sticky somewhere on the site so it doesn't get buried :-)
  • jkhoward
    Quote:
    "the power supply is actually one of the more important parts of a build" Thank you!! Or rather, let's do what the cool kids are doing and rather post a GIF: https://giphy.com/gifs/the-office-thank-you-michael-scott-1Z02vuppxP1Pa


    Seriously, not enough people realize how import a good PSU is. I am working with someone is heavily overclocking an i7 and two 970 in SLI as well as 4 SSD and a few hard drives, a bunch of fans, with a 750W PSU.
  • jkhoward
    Also... I am digging the age of some of these images.
  • blackmagnum
    This article brings back embarrassing memories. https://giphy.com/gifs/the-office-thank-you-michael-scott-1Z02vuppxP1Pa
  • alidan
    Quote:
    Quote:
    "the power supply is actually one of the more important parts of a build" Thank you!! Or rather, let's do what the cool kids are doing and rather post a GIF: https://giphy.com/gifs/the-office-thank-you-michael-scott-1Z02vuppxP1Pa
    Seriously, not enough people realize how import a good PSU is. I am working with someone is heavily overclocking an i7 and two 970 in SLI as well as 4 SSD and a few hard drives, a bunch of fans, with a 750W PSU.


    unless i'm thinking wrong, isn't that within the power limits of a 750? im even assuming that each gpu is 300 watts and i know they shouldn't hit that even with the most aggressive of ocs

    granted there is a distinction between a good psu and a bad one, but im just assuming its a good one.
  • chimera201
    Motherboard slots haven't evolved much. Wished every slot was like a USB slot
  • turkey3_scratch
    612443 said:
    Seriously, not enough people realize how import a good PSU is. I am working with someone is heavily overclocking an i7 and two 970 in SLI as well as 4 SSD and a few hard drives, a bunch of fans, with a 750W PSU.


    Your point being... ?
  • renosablast
    Steps 1 and 3 should be combined, and step 2 comes after 1 and 3. You better worry about the CPU and motherboard combo compatibility before you worry about a graphics card.
  • renosablast
    Sorry, meant steps 2 and 4 before 3.
  • Dark Lord of Tech
    I love when you see a $1500.00 build with top quality components and then they have a $40.00 PSU listed with it.
  • Outlander_04
    IMO the very first component selection for a gaming build should always be the .... MONITOR.
    Decisions on where and how to spend the rest of the budget can only be made once you know the resolution , and whether its 60 Hz, 144 Hz or whatever else is available
  • MasterMace
    Gonna throw in my disagreement on the priority, mentioned nice and early in the article. The first thing you pick is never your case. There's 3 things you can decide to be your starting point when building a pc to make it a smooth ride; either, 1. Budget. 2. CPU 3. Graphics. By picking 1 of these 3 things as your starting point, you can have a very smooth build process. Does that mean you buy your case last? No, I've seen plenty of builds where the case arrives first as a way of storing the items, but when you want a solid build, your case is last priority, as it has no impact on your performance and restricts the size of your items.

    Even if you wanted to build an odd form factor, like an itx, you would still pick the cpu or the budget before the case.
  • Thank you for explaining ESD correctly. I have been annoyed with articles over exaggerating about ESD a lot. So just touching something metal can help? Well, next time I think I'll set a PC on my wooden desk instead of the carpet.
  • kunstderfugue
    Quote:
    I love when you see a $1500.00 build with top quality components and then they have a $40.00 PSU listed with it.


    The XFX TS Bronze 550 comes down to $43 ish from time to time and that's a mighty fine PSU to power a single graphics card build.
  • nitrium
    Quote:
    "the power supply is actually one of the more important parts of a build" Thank you!!

    While not unimportant, it gets far too much attention on the forum's here. PSU's are only relatively rarely the cause of issues, and I'll go out on a limb and say that virtually ANY modern 650W PSU (even ultra-cheap China garbage) will reliably power a single GPU and CPU, regardless of model or how much OCing you do to them.
  • Crashman
    269694 said:
    Quote:
    I am working with someone is heavily overclocking an i7 and two 970 in SLI as well as 4 SSD and a few hard drives, a bunch of fans, with a 750W PSU.
    unless i'm thinking wrong, isn't that within the power limits of a 750? im even assuming that each gpu is 300 watts and i know they shouldn't hit that even with the most aggressive of ocs granted there is a distinction between a good psu and a bad one, but im just assuming its a good one.
    You're exactly right. We've been using high-quality power supplies in most of our System Builder Marathon machines, and dual 970s was in one of the builds. The super-high recommendations you see from other sites are a response to most builders using mediocre-quality units.
  • Crashman
    416912 said:
    Gonna throw in my disagreement on the priority, mentioned nice and early in the article. The first thing you pick is never your case. There's 3 things you can decide to be your starting point when building a pc to make it a smooth ride; either, 1. Budget. 2. CPU 3. Graphics. By picking 1 of these 3 things as your starting point, you can have a very smooth build process. Does that mean you buy your case last? No, I've seen plenty of builds where the case arrives first as a way of storing the items, but when you want a solid build, your case is last priority, as it has no impact on your performance and restricts the size of your items. Even if you wanted to build an odd form factor, like an itx, you would still pick the cpu or the budget before the case.
    Exactly wrong. The first thing people do is say "I want a LAN box" or "I want a media player" or "I want a big gorgeous office PC". They're picking a case SIZE when they make those FIRST statements, so size comes first in the discussion.
  • beoza
    Quote:
    416912 said:
    Gonna throw in my disagreement on the priority, mentioned nice and early in the article. The first thing you pick is never your case. There's 3 things you can decide to be your starting point when building a pc to make it a smooth ride; either, 1. Budget. 2. CPU 3. Graphics. By picking 1 of these 3 things as your starting point, you can have a very smooth build process. Does that mean you buy your case last? No, I've seen plenty of builds where the case arrives first as a way of storing the items, but when you want a solid build, your case is last priority, as it has no impact on your performance and restricts the size of your items. Even if you wanted to build an odd form factor, like an itx, you would still pick the cpu or the budget before the case.
    Exactly wrong. The first thing people do is say "I want a LAN box" or "I want a media player" or "I want a big gorgeous office PC". They're picking a case SIZE when they make those FIRST statements, so size comes first in the discussion.


    I have to agree with you on this Crashman. Whenever I go to build a new system for friends or relatives I always ask what they're going for in terms of use. I like to go with the Form follows function principle which is that the shape of a building or object should be primarily based upon its intended function or purpose.
  • Libero
    Quote:
    Gonna throw in my disagreement on the priority, mentioned nice and early in the article. The first thing you pick is never your case. There's 3 things you can decide to be your starting point when building a pc to make it a smooth ride; either, 1. Budget. 2. CPU 3. Graphics. By picking 1 of these 3 things as your starting point, you can have a very smooth build process. Does that mean you buy your case last? No, I've seen plenty of builds where the case arrives first as a way of storing the items, but when you want a solid build, your case is last priority, as it has no impact on your performance and restricts the size of your items. Even if you wanted to build an odd form factor, like an itx, you would still pick the cpu or the budget before the case.

    Quote:
    Sorry, meant steps 2 and 4 before 3.

    It is same meaning as define a purpose and choose a case. When you buy a computer you must know what the purpose for first example for home/office, web browsing, gaming or multi-tasking. Budget also is depend to each person. So it is not CPU or GPU before case.
  • James Mason
    I wish the pictures of PSU weren't just all Corsairs. That leads people to believe that all Corsair PSUs are "good" PSUs, when we know a vast majority aren't, and the ones a new builder are most likely to be definitely aren't.
  • Crashman
    297651 said:
    I have to agree with you on this Crashman. Whenever I go to build a new system for friends or relatives I always ask what they're going for in terms of use. I like to go with the Form follows function principle which is that the shape of a building or object should be primarily based upon its intended function or purpose.

    It is same meaning as define a purpose and choose a case. When you buy a computer you must know what the purpose for first example for home/office, web browsing, gaming or multi-tasking. Budget also is depend to each person. So it is not CPU or GPU before case.
    Yeh, I should have just kept his last statement and deleted the rest before responding:
    416912 said:
    Even if you wanted to build an odd form factor, like an itx, you would still pick the cpu or the budget before the case.
    What he's saying is even if you choose a form factor first, you're still buying the other parts first. Which is a backwards way of saying that the order of the article, form factor first, makes sense...and he still wants to disagree...

    The problem is that one needs keep a general concept of the case in mind when picking the actual components. One can often pick the exact case to fit that concept at the end, but the "Define a purpose" leads immediately to form factor, and chopping the article off there only to come back to case selection doesn't really make sense.
  • Bjorn_2
    I miss one important piece of advice: do not install anyhting but your primary drive before installing Windows. I have recently gone through the nightmare of trying to aggregate Windows onto my primary drive when replacing my SSD for a bigger one. It seems that if you have multiple drives installed, windows will happily use all for various purposes. So feel free to install everything but please, before installing Windows, disconnect your secondary and other drives.