If you’ve just got a new PC, connected everything, booted up the system, fired up your favorite game, and realized it runs super slowly, you might’ve made an honest mistake that many new PC gamers make.
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You might’ve plugged the monitor cable into the wrong port
The most common mistake many new PC gamers make, which causes games to run slow or not run at all, is plugging the monitor cable into the wrong port. To see if that’s the case with your PC, just check the back of your computer.
You should see something similar to the photo below. At the top, we’ve got a bunch of ports. USB ports, a couple of video ports, along with two RJ-45 (Ethernet) ports (some boards come with one), a number of audio jacks, and perhaps some other connectors. These are all your motherboard’s ports. Below the motherboard, you should see a collection of video outputs, usually DisplayPort and HDMI. These are your graphics card’s ports.
Your monitor cable should be connected to one of the dedicated ports on your GPU. If it isn’t, and is instead plugged into a motherboard port, that’s likely why the PC is performing sluggishly. Since the cable is connected to the motherboard, the PC is using the CPU’s integrated graphics instead of your graphics card, which is much slower and, in most cases, can’t run even undemanding 2D games very well.
What you should do is turn off the PC, unplug the cable from the motherboard, and plug it into one of the graphics card’s ports.
Just check which port the monitor cable ends in (HDMI or DisplayPort), then plug it into the appropriate port on the graphics card. That should be it!
There are other potential reasons why your PC is running slowly
If your monitor cable has been plugged into the GPU from the start, there are other issues that may cause games to run slow on your PC.
Your CPU might be overheating
The second most common issue causing slow gaming performance on new PCs is a CPU that’s thermally throttling, which can make it run much slower than it should.
CPU thermal throttling can have multiple causes. A common one is you, or the person who built the PC, forgetting to remove the plastic sticker covering the bottom of the CPU cooler that comes into contact with the CPU.
To test whether your CPU is thermal throttling, download a system monitoring app, such as HWiNFO, along with a CPU benchmarking tool, such as Cinebench. Install and open HWiNFO, and scroll down until you see the section that shows CPU temperature info.
Now launch Cinebench and run the multi-core CPU benchmark.
Monitor the CPU temperature during the benchmark. If it quickly reaches 100°C, your CPU is throttling. This could be due to the sticker not being removed, as well as other causes.
For instance, the CPU cooler might not be properly seated, resulting in less than ideal contact with the CPU, which can also lead to thermal throttling. There’s also a slim chance that too little thermal paste has been applied to the CPU’s surface. Lastly, the CPU cooler might not be powerful enough to rein in the CPU.
Whichever the case, the course of action would be to either remove the CPU cooler yourself and check whether the plastic sticker is removed or to reseat the cooler. Alternatively, you could call the store or manufacturer you bought the PC from and arrange for a pickup, or a visit from a technician. You could also carry the PC back to the store yourself.
Your RAM might not be properly seated
Not having enough RAM can make games run very poorly. One moment, the game you’re playing can run great, and the next, it might start constantly hitching because there’s not enough memory for the game assets to load in as you move around the game world.
If your PC has two memory sticks, one might not be properly seated, so the PC will only recognize half of your memory. If the PC has 32GB of RAM or more, a single stick of memory not being seated correctly shouldn’t cause games to run slowly, since 16GB of RAM is more than enough for most games. But if you’ve only got 16GB of RAM in total, it’s worth checking whether your RAM is properly installed.
You can inspect whether both your RAM sticks are properly installed in Task Manager. To open the app, right-click an empty space on the taskbar, then click “Task Manager.”
Select the “Performance” menu and then click the “Memory” tab. If the total amount of memory doesn’t match your PC’s specs, one of the sticks is probably not installed properly.
You can reseat it yourself if you know how, or contact the company you got the PC from if you aren’t comfortable doing it or don’t want to void the warranty. Below you can watch a step-by-step tutorial on reseating RAM, courtesy of the META PCs YouTube channel.
Your internet connection might be unstable
If single-player games run fine, but you experience problems with multiplayer games, your internet connection might be the culprit. More accurately, the connection between your PC and the router might be unstable.
You can check this by looking up your ping in multiplayer games you play, or by using an online ping test such as the one available on the ping-test website. Anything above 100 milliseconds (ms) can cause visible lag spikes. A ping of 200ms or higher will likely cause significant lag and stuttering, and can make the game completely unplayable.
If you’re connected to your router wirelessly, the best way to improve connection quality is to switch to a wired Ethernet connection. If that isn’t possible, there are a number of ways to improve the quality of your wireless connection.
While these are the most common reasons why games run slowly on your new PC, the list of potential issues is far longer. For instance, there’s a small chance that your SSD is faulty, which might allow you to use Windows but can have a detrimental effect when running demanding programs, including games.
Sluggish performance in games could also stem from issues with GPU drivers. You can remedy this by updating your graphics drivers. If that doesn’t solve it, you ought to clean install the GPU drivers. If your PC worked fine, but slowed down after a Windows update, you can try speeding it up.
