If you're a PC gamer with a high-end rig, you're probably familiar with the wonders of high refresh-rate gaming. The feeling of smoothness you feel whilst gaming at 120, 144, or even 240 FPS can be quite fantastic, and it's pretty tough to give up. Unfortunately, some games force you to do just that.
Bethesda titles, in particular, are notorious for having their physics engines (among other things) locked to the player's framerate. This means that, if you go over 60 FPS, you'll start to notice quite a few oddities. At lower framerates, they aren't as noticeable, but once you exceed 100 FPS or so, you'll see enemies fly into the sky, objects hurl themselves off of tables, and horses glitch into mountains.
There is a community-discovered fix for these issues (it works for Skyrim, Skyrim Special Edition, and Fallout 4), but it isn't widely-known, and most players simply cap their FPS to 60 to avoid the situation entirely.
Sadly, it seems Bethesda is not the only developer whose games suffer from framerate-related problems. According to Reddit user Jimmyoneshot, Red Dead Redemption 2's PC port also ties certain aspects of gameplay to player framerates. After what appears to be some pretty thorough testing, Jimmyoneshot found that in-game protagonist Arthur Morgan's Health and Stamina meters, as well as his weight, are drastically affected by the game's FPS.
If you run the game at 30 FPS, everything will be normal. You will lose weight just as you would in RDR2's console versions. However, if you run the game at 60 FPS, Core drain speed and weight loss will be twice as fast, meaning you'll need to eat 2x as much food as you normally would to keep things steady. At 120 FPS, your stat drain speed is reportedly quadrupled, and so on.
If that wasn't bad enough, Jimmyoneshot's fellow redditors have reported other FPS-related issues as well. While there don't seem to be any major, game-breaking physics bugs at high framerates, RDR2's mostly-cosmetic weather and day/night cycles are affected. Some users say heavy storms will roll in and out in as little as 30 seconds, which certainly isn't intentional behavior (I've played the game on console myself, and adverse weather usually lasts much longer than that).
We've reached out to Rockstar for confirmation on this bug, and we'll update you when or if they respond. Playing at 60 FPS (or more) is one of the primary benefits of playing RDR2 on PC, and it'd be a shame if players were punished -- even unintentionally -- for doing so.
It's worth noting that these framerate headaches are far from the only ones RDR2's PC fans have dealt with recently. When the port first launched a few days ago, it was plagued with numerous performance-related issues, from stuttering to poor overall optimization. Thankfully, some of the complications have been fixed with new driver updates, but it's clear the game still has a ways to go.