Frame rate can sometime affect gameplay where you least expect it. Take Resident Evil 2 for instance, where it was recently discovered that higher frame rates equal more damage dealt with the combat knife.
Redditor TheInfamousDH published the findings of an experiment they conducted in Resident Evil 2 on Reddit that revealed that knife damage is related to frame rate. TheInfamousDH wanted to find out how some video game streamers were able to kill the G1 William Birkin boss in so few knife hits, while they were struggling to make it through the battle unscathed.
They surmised that frame rate might be a factor and decided to test this theory by playing through the same G1 Birkin boss fight in Leon's Standard A route with both Vsync on, and Vsync off with a variable frame rate.
What they discovered is that at 60fps, it took exactly 45 slashes with the knife to kill Birkin, regardless of where the slashes hit the target. But at around 180fps it took about 25 slashes to kill Birkin. TheInfamousDH says they were able to replicate these results five times each after only changing the frame rate settings.
After additional testing, TheInfamousDH also found that at 30fps they were unable to even kill Birkin after slashing at him more than 56 times. But at around 230fps Birkin went down after about 21 hits.
Users on the Reddit thread are suggesting this is because damage with the knife is tied to each frame it passes through a target, meaning more frames would equal more damage. One person in the thread says that at even higher frame rates it might be possible to take down Birkin in just a couple hits.
So, if you're trying to go for a knife-only speedrun through Resident Evil 2, it might be a good idea to keep the game running at uncapped frame rates—granted you can get your frames per second high enough to deal massive damage quickly.