Published On: Sep 16, 2019
So you've installed all your PC parts and think you're ready to boot your new PC build for the first time. However, if you want to make sure you've done all the required steps and completed everything that you need to do correctly for a stress-free, smooth and successful first boot, in this guide we'll quickly go over a basic checklist before pressing that magical On button and starting-up your new computer.
You'll first want to double check all your components are all still inserted all the way into their slots and firmly held in place via screws and/or their socket clips. It's unlikely, but during the installation of your motherboard into the case or while you plugged in all the power cables into the motherboard, a component may have accidentally been moved around a little or disconnected if it wasn't properly fitted and/or screwed in.
Loose screws may lead to a component being loosed in its motherboard socket, so it's worth double checking now. Remember not to tighten screws too far; just turn them a fraction more than when they feel tight. Go ahead and check your CPU cooler, memory module/s, graphics card/s, and any other components you have in your motherboard.
Double check the front panel connections that you plugged in earlier in the building process, as there is the chance something may have become loose during later steps. While you're at it, double check all of your power supply cables are firmly plugged into place.
If you connected your power supply cables a while back in the process, or you've since been digging into some cable management 'cause you know what's good for you (and your system), you might as well double check those cable connections as well to ensure all power cables are securely connected all the way in to your motherboard (and any other components that require a direct connection from your PSU).
Ok, it's time to connect up your peripherals so that you can see what happens on-screen when you first boot-up, and so that you can proceed with installation should your PC start up properly the first time.
The keyboard and mouse should plug into any USB ports; ideally you'll want to plug them in the back of your PC to keep your front ports available. Older keyboards and mice will plug into the PS/2 connections instead, also on the back of your PC.
Depending on the monitor, you will either need just the video cable (either HDMI, DVI, DP or VGA) from the back of the monitor into the back of your graphics card (not your motherboard), or you'll need both a video cable and a dedicated power cable connection from the back of your monitor into a wall socket.
If you have a set of speakers or using a headset, you can plug these in now if you want to. Same with your network connection; an Ethernet cable will plug from the back of your PC to your router, or if you're using a wireless dongle then plug that into the back.
Replace your case's rear side panel if you haven't already done so. However, keep the main side panel off for the time being so you can see what's going on when you boot-up in the next step.
Then plug in the main power cable of your power supply to a wall socket (ideally into a surge protector of some sort if you have one), and turn the power on at the wall.
Now, turn on the switch on the back of your power supply, and turn on your monitor.
You now have everything ready to go, so it's time to cross fingers, pray to the skies, and press that scary On button on the front of your case.
If you've done everything correctly throughout the PC building process, which you should have if you followed a full step by step guide like ours, you should now hear your case fans start up (hopefully only lightly because nobody likes a loud system), and you should also see a light on your PC and on your motherboard (some boards may not have a light though).
Something should show up on your monitor, too (make sure the monitor is turned on). Look inside your case to check that your case fans and the CPU fan is spinning. Keep in mind that your graphics card fan/s may not spin unless they're under load, so don't worry if there's no sign of life in that department.
If everything seems to be working, replace your side panel as you shouldn't run your PC without both panels in place for too long as it affects airflow.
More importantly, high five yourself or the nearest feline/dog/dude/dudette because you've now successfully built your first PC and ascended to rank of Jedi within the Master Race of gaming (which is PC for anyone who's been chilling under that proverbial rock for the past decade).
Or, if you've been using our gaming PC installation guides instead as a refresher (and you've already built a PC in the past)...give yourself (or that cat) a high 4.
Once you successfully do a first boot of your computer and all seems well, it's time to wade into the notorious waters of the BIOS and install your operating system software.
If there's no response when you turn on your PC, or something seems to be wrong, you're going to have to track back over your steps to see whether you missed something, didn't connect something properly, or to find another issue. Worst case is that a component isn't working and you can simply return it for a replacement, which really isn't that bad and does happen sometimes.
Don't get down on yourself or stress out if your new computer doesn't turn on, as it could be something very simple that you either missed or that you can quickly rectify, and you should be up and running in no time to claim that Jedi status.
We won't leave you hanging: see the troubleshooting new PC builds guide to learn how to find and fix common first-boot problems.
PC Assembly Hub: How to Assemble a PC
Need Help Choosing Parts?
Don't miss our flagship guide, The Best Gaming PC Builds for the Money, which pinpoints the current best value parts for Q1 2021, and feel free to ask for help in the comments section if you get stuck along the way.