Does running applications in background on Windows 10 machine when playing full screen FPS game affect performance?

Does running applications in the background on a Windows 10 machine when playing a full screen FPS game affect performance?

For example, I'm playing Squad now on and I sometimes have Chrome open in the background, but it's not clear to me if that can affect frame rate significantly.

It depends.

Everything that's running on your PC will make use of some resources, which means your game won't be able to access those resources. However, if your game doesn't actually need them, it won't be affected much if at all.

So it all depends on how powerful your PC is, how much (and what kind of) resources the game needs, and how much (and what kind of) resources are currently in use by other processes.

There are 3 ways a program can affect a game's framerate. In no particular order:

1. RAM (Random Access Memory). As long as there is enough RAM, your framerate won't change at all. If there isn't enough — even if only by one Byte — it can significantly affect your framerate, either all the time, or only in specific situations.
2. CPU. If you have more cores than the game can use, and as long as there aren't too many CPU-heavy applications running, you should be safe.
3. GPU. Usually has the most immediate effect on framerate, but isn't used by many programs (especially not ones running in the background).

In most cases, apps running in the background shouldn't affect gaming performance much, unless your PC is very weak and barely meets the game's requirements. Browsers are a bit of a special case, however.

First of all, when using browsers, every site you visit can be considered to be a program by itself. That is, each site (running in each tab) requires RAM. They can each have JavaScript running, which puts load on the CPU. And with WebGL, they can each access the GPU; even without WebGL, they can make use of GPU resources (through CSS animations, for instance).

The best way to know if your browser is impacting your framerate, is benchmarking: Run the game both with and without Chrome running, compare the performance, and decide whether the perceived loss of performance is acceptable or not.

Alternatively, you can open the Task Manager (right-click on your Taskbar -> Task Manager) and see how much resources your browser currently uses. In my case, it uses between 1 and 2% CPU, 0% GPU, and a little above 3GB Memory (RAM). That's a lot of RAM being used, but since my PC has 32GB to spare (and most games don't ask for more than 8GB), my browser's impact on gaming performance should be negligible.

Your framerate can be limited by a lot of things involving your hardware and software, and while the most common factors involve CPU, GPU, and RAM, it can get a little more complicated. Genre of game only makes a little bit of a difference.

A. GPU Performance

• The primary factor in most video game performance issues
• Is really only used by the fullscreen application, as the OS culls sending information about graphics it's not displaying to the video card (unless the software is really badly programmed).
• Has three major factors which affect it.
  1. Heat: if the card overheats, artifacts can appear in your graphics or framerate slows to a crawl. Unless overclocked, this is a sign of insufficient cooling. If overclocked, it can also be a sign of overvolting the GPU. The GPU is like a CPU dedicated only to doing the math that creates all of the shapes and models on your screen, so anything which hurts a CPU hurts a GPU.
  2. Graphics Memory (VRAM). The more that a graphics card is displaying at once and the higher the resolution of the textures, the more of this is taken up. These can be affected by heat as well, but the problem is usually capacity. Video cards under 4GB should not attempt 4k resolutions in most cases.
  3. Driver settings. Always make sure you use the latest version of the drivers for your card, as these have optimizations which clean up problems found by the card manufacturer when testing against new games.

B. CPU Performance

• Handles processing everything in the computer. Handles everything on "threads" which are a series of instructions for the computer to perform. More than one processor core allows more than one instruction per cycle. The average i7 processor has 4-8 cores.
• Most games only use one thread, even some of the newer ones. This means that a backup in processing due to speed or processor load from other apps being open can slow performance.
• Small apps have no real impact on performance. Youtube and other media sites use media players that take up a bit more, but it's usually negligible. Running 2 single core games at once on the same core or multiple core games in combination with anything else demanding will cause slowdowns.
• CPUs are VERY SENSITIVE TO HEAT. That is why overclockers often use expensive aftermarket cooling, such as heat sink blocks and water cooling systems, to protect the hardware. If a CPU begins to overheat, framerates drop and many other problems can arise.

C. RAM

• Computer short-term memory. The more you have, the more data can be loaded for use from longer-term storage.

• Is accessed very quickly and can be impacted by heat, but runs cooler than a CPU

• Running multiple applications that are not CPU demanding can still cause issues here, as every application must load its data into RAM during runtime. A modern i7 is usually fine with 8-16GB of RAM unless you're running 5 browsers, a game, and Blender all at once. My most intense 64-bit game only takes up 9.5GB of my RAM and leaves plenty to spare, and that's due to heavy modding.

• 32-Bit games (older games and many recent ones) will only ever use 3GB of RAM to run due to limitations on 32-bit applications. Two 32-bit apps running at max memory usage can take up 6GB combined. This shouldn't be an issue on a modern computer.

D. STORAGE MEDIA Performance

• Hard Disk read times are the nightmare that creates the "Loading..." screen. They are a mechanical combination of machinery and magnetism that takes time to locate the data on the disk.
• Solid State Disks read almost instantly, as they have no moving parts to speak of and read directly from NAND chips.
• Issues with the disk interface point, such as a SATA cable or port on the motherboard, can impact performance
• Trauma from dropping can destroy an HDD or riddle it with "bad sectors".
• HDDs "fragment" data over time and need to be "defragmented". If you do not, and run a game from an HDD, then load times and frame rates can both be affected.
• The more data is on an HDD, the longer it takes to read data from that HDD. If you have a 5TB drive that is nearly full, loading textures from the HDD to the RAM and VRAM can take more time, especially if the drive is fragmented.
• Heat can also drastically affect the performance of an HDD and moderately affect the performance of an SSD.
• Other tasks on the HDD massively affect performance. The head on an HDD is limited as to what it can read, so long-running HDD reading processes can bog down a hard disk and spike access times.

E. Network Connection

• Only really an issue if you're online gaming OR
• If you have a long running task, like a large download.
• Most online games use around 1Mb/s transfer rates. if your connection is having problems, this will cause framerate issues.
• A computer set to aggressively reconnect a failed connection may interfere with game performance in its attempt, as this will make calls to the CPU to release and renew connections.

F. Malware

• Sometimes, something wicked is using those CPU cycles.
• Go through everything running and make sure you can identify the processes in the Details tab. If you see any suspects, run your AV program.
• Chrome plugins can go nuts on you. If you see 20 instances of Chrome open, probably time to close it down and make sure all of those instances close with it.
• Run a boot-time scan to be sure.