So you've decided to finally play or replay the game with your current rig, which has hardware newer than AC: 3. You might have played the previous ones and had no problem, right up until you load up AC: 3 and the menus is shaking and the game is full of weird bugs. Below you have the solution, step by step, with pictures.

AC:3 is an older title, it's from 2013 well before high refresh rate monitors were common place. Sadly AC:3 is not a game you'll be able to play at a high refresh rate. In fact the game expects a refresh rate of 60 and used forced vsync to limit the fps to 60. The quick and dirty fix is to just change windows refresh rate to 60 and you're good but that would get annoying having to switch it every time you want to play and then back for other games. My preferred way is to leave the refresh rate as is and just limit the frame rate for the game.

This guide will be for NVIDIA, sorry AMD users this won't help you but one[www.amd.com] of these[www.amd.com] might.

If an amd user wants to provide screenshots I'll update the guide or they could post an amd specific guide.

The quickest way I've found to do this is to use the software provided by nvidia, if you don't see these settings make sure your driver is up to date.
What you're going to want to do is close the game if you have it running and open the nvidia control panel:


In the control panel go to the manage 3D settings page then click the program settings tab:


If you don't see AC:3 in the drop down click add. If you've recently played the game it should appear near the top as AC3SP.exe otherwise click browse and and find that exe in your install location.


Find the setting called Max Frame Rate and set it to 60:

Another thing I found that helps with stability in the game is forcing vsync while in the control panel:

Another thing that seemed to help crashing issues was using these compatibility options:

It seems that parts of this game are tied to fps, until limiting the fps I would find models (wagons especially) failing to load, ragdolls would freak out and contort wildly, the screen and menus would flicker like crazy and the game would crash every 5-10 mins. I can't blame ubisoft too much since 60fps was the standard when this game came out and high refresh rate wasn't even a though in most gamers minds.

NOTE: With this fix there is a chance there will still be a weird camera shake in the menus and in game. I've found that exiting and reopening the game fixes this.