Out of every AC game I've played, this one is the most poorly optimized. I have a very good gpu and my computer is powerful enough that it should run flawlessly. This is not the case. Maxes out my gpu when it shouldn't, lags so badly, I feel like I'm playing in Microsoft Powerpoint. I even tried playing on the lowest settings. Not a single change. Never should have been released on PC.
Hey @Core_Dragon! And you too @XBL_Laberbacke. 
I'm quite sorry to hear that you're running into these issues even on the lowest settings and would like to do what I can to see if we can get this running a little better for you.
If you haven't already, try verifying your files and clearing your Ubisoft Connect cache. If that doesn't help then you can run through what's left in our handy troubleshooting guide here that's known to help with issues much like your own.
Should you have any further trouble with it after going through those steps, you can go ahead and attach your System Files to a Support Case and I'll be more than happy to take a closer look into what's happening with you.
devtrackers.gg