The most common PC performance issue takes just five seconds to fix
If you just got a new PC, plugged everything in, booted up the system, launched your favorite game, and realized that it’s running very slowly, you may have made an honest mistake that many new PC gamers make.
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You may have plugged the monitor cable into the wrong port
The most common mistake many new PC gamers make that results in games running slowly or not at all is plugging the monitor cable into the wrong port. To see if this is the case with your PC, simply check the back of your computer.
You should see something similar to the photo below. At the top we have a bunch of ports. USB ports, a few video ports, as well as two RJ-45 (Ethernet) ports (some boards have them), a number of audio jacks, and perhaps other connectors. These are all the ports on your motherboard. Underneath the motherboard you should see a collection of video outputs, usually DisplayPort and HDMI. These are the ports on your graphics card.
Your monitor cable should be connected to one of the dedicated ports on your GPU. If it doesn’t and it’s plugged into a port on the motherboard, that’s probably why the PC is running slowly. Since the cable is connected to the motherboard, the PC uses the processor’s integrated graphics card instead of your graphics card, which is much slower and, in most cases, cannot run even undemanding 2D games very well.
What you need to do is turn off the PC, unplug the cable from the motherboard and plug it into one of the ports on the graphics card.
Simply check which port the monitor cable terminates 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 was plugged into the GPU from the start, there are other issues that can cause games to run slowly on your PC.
Your processor may be overheating
The second most common problem causing slow gaming performance on new PCs is a processor experiencing thermal throttling, which can make it run much slower than it should.
CPU thermal throttling can have several causes. It’s common that you, or the person who built the PC, forgot 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 experiencing thermal throttling, download a system monitoring application, 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 displays CPU temperature information.
Now launch Cinebench and run the multi-core CPU benchmark.
Monitor the CPU temperature during the benchmark. If it quickly reaches 100°C, your processor is slowing down. This may be due to the sticker not being removed, as well as other causes.
For example, the CPU cooler may not be seated properly, resulting in less than ideal contact with the CPU, which may also cause thermal throttling. It’s also possible that too little thermal paste was applied to the processor surface. Finally, the CPU cooler may not be powerful enough to overpower the CPU.
Whatever the case, the solution would be to either remove the CPU cooler yourself and check to see if the plastic sticker is removed, or reinstall the cooler. You can also call the store or manufacturer you purchased the PC from and arrange for a pickup or a technician’s visit. You can also return the PC to the store yourself.
Your RAM may not be installed correctly
Not having enough RAM can make games very bad. At one moment, the game you’re playing might be running just fine, and the next, it might start crashing constantly because there isn’t enough memory to load the game’s resources as you move around the game world.
If your PC has two USB drives, one of them may not be installed correctly, so the PC will only recognize half of your memory. If the PC has 32 GB of RAM or more, a single incorrectly installed memory stick should not slow down game performance, as 16 GB of RAM is more than enough for most games. But if you only have 16GB of RAM in total, it’s worth checking if your RAM is installed correctly.
You can check if both your RAM sticks are installed correctly in Task Manager. To open the application, right-click an empty space on the taskbar, then click “Task Manager.”
Select the “Performance” menu then click on the “Memory” tab. If the total amount of memory does not match your PC’s specifications, one of the keys is probably not installed correctly.
You can reinstall it yourself if you know how to do it, or contact the company you purchased the PC from if you’re not comfortable doing so or don’t want to void the warranty. Below you can watch a step-by-step tutorial on reinstalling RAM, courtesy of the META PC YouTube channel.
Your Internet connection may be unstable
If single-player games work fine, but you’re having issues with multiplayer games, your internet connection could be the cause. Specifically, the connection between your PC and the router may be unstable.
You can check this by looking up your ping in multiplayer games you play or using an online ping test such as the one available on the ping-test website. Anything over 100 milliseconds (ms) can cause visible lag spikes. A ping of 200ms or more will likely cause significant lag and stuttering, and can make the game completely unplayable.
If you are connected to your router wirelessly, the best way to improve connection quality is to upgrade to a wired Ethernet connection. If this is not possible, there are several 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 problems is much longer. For example, your SSD may be faulty, which may allow you to use Windows but may have an adverse effect when running demanding programs, including games.
Slow game performance can also be caused by issues with GPU drivers. You can fix this by updating your graphics drivers. If this does not resolve the issue, you should reinstall the GPU drivers. If your PC worked fine, but slowed down after a Windows update, you can try speeding it up.
