OS: 8.1

CPU: Intel i5-4460 @ 3.2 Ghz

Ram: 8 Gb DDR3, 1600 hz

GPU: R9 380 4gb Gaming

Unless I turn off V-sync, I get low frames regardless of low/med/etc. settings. I would rather leave it on, as I only have a 60hz monitor and I know turning that off can screw with the game. The lockpicking game for example is VERY fast.

What would be some recommended tweaks? (I already set God Rays to low and Shadow distance to medium)

Also, how is windows 10 for gaming? Pop up is getting annoying and there is only a few months left before the free upgrade expires.

If you mean the pop up notification for upgrading to W10 look here:

http://www.pcadvisor.co.uk/how-to/windows/how-remove-windows-10-nag-messages-not-madatory-3614204/

Not that I have played a lot of games on W10, the ones I have have had no issues.

Frankly I like W10. I don't like the intrusiveness of it but that can be dealt with with programs like https://www.oo-software.com/en/shutup10 or similar.

I recommend people upgrade. It does not prevent you from going back to your current OS. It does not invalidate the current OS' key nor does W10 need a key of it's own. (Once installed, you own it for that rig and can install it anytime.) If you decide you don't like it you can either re-image (if you make an image of the current OS first of course.) your current OS or simply reinstall it. I recommend imaging the drive. Makes for a much simpler "install" as it's already set up the way you like it. I use the free version of http://www.todo-backup.com/download/ to image my drives.