Why would you want to limit your frame rate in BF3? More FPS is better, right? Not always.
Let’s say your PC is capable of averaging 70 FPS. Most monitors are limited by a refresh rate of 60Hz, which means it’s really only showing you 60 FPS.
Your graphics card(s) will still pump out 10 extra frames per second, even though you don’t see them on your monitor. A system that is running at full load will draw more electricity, produce more heat, and require the fans to run faster/louder.
If you limit your frame rate to 60 FPS, that’s all your computer will render. Your PC will no longer need to run at full load if it’s capable of producing more than 60 FPS at any given time. This means less power, heat, and noise.
First, you should display your FPS ingame. To do so, press the tilde ( ` ) key. Type the command render.drawfps 1 and press Enter. Your framerate will appear at the top right.
If your PC is fairly high-end, you will see the frame rate exceed 60 FPS some of the time you’re playing. This happens most when you’re inside a building without much action going on.
To limit your frame rate, type gametime.maxvariablefps 60 in the console and press Enter. From that point on, the FPS number in the top right should never exceed 60. Your video will look just as good as before, but with less of a load on your PC.