It isn't a problem with the game. You have a 60hz monitor. Vsync is on by default in Fallout 4. With a 60hz refresh rate monitor and Vsync on it is impossible to get more than 60fps.

And since physics simulation is AGAIN tied to framerate in Fallout 4, you really don't want it running above 60fps, or stuff starts to get weird.

Unless I manually turned on vertical sync, my frame rate was over 100 fps. Although, my monitor runs as 144Hz, so that could be the issue.

Once I turned on v-sync, I run locked at 60 fps .

My Motherboard is an ASUS ROG MAXIMUS VII HERO LGA 1150 Intel Z97, PCI 3.0 and I built the machine myself. The monitors are older but I don't see how that would drop my framerate from 60fps to 30 fps. I have V-sync turned on.

I fixed my issue, it was the driver. I updated it on 11/9 and I guess Nvidia put out a new one today that locks my framerate at 60 FPS and it looks amazing. So to the OP, go update your drivers to the newest "Game ready" driver and that should fix your issue. Thanks to everyone that gave advice.

Guys, the game has a default 60 FPS cap.
Removing it (iPresetInterval = 0) is a bad thing because any framerate spikes to 200 or 250 FPS will mess up the game's physics.

Most monitors refresh @ 60Hz. Therefore you don't need more to achieve VSync.
It is your MINIMUM framerate that should concern you!
In other words, will it ever drop below 60 FPS?
Wanting to "show off" your vidcard by removing the cap is wrong-thinking...
Let your rig show off by never, ever going below 60 FPS.

If you want 120 FPS (and some monitors refresh at 120 or even 144) you can change iPresetInterval to 2.
Gonna be a manly vidcard that'll VSync that though, heheh...

Note: when you have VSync enabled, if your frames ever go below 60 FPS they will drop to 30 FPS right away (not like 59 or 58 etc.)
So if you're NOT pulling 60 FPS average, you should probably turn off the VSync.
nVidia Adaptive Vsync is great! Above 60 FPS, VSync is on. But if it falls below 60, it switches VSync off automatically.
So you'll get 55 or 50 FPS or whatever, and screen tearing. But hopefully only temporarily.
Your minimum FPS is far more important than your maximum! Don't forget.

"The thing is, my framerate peggs out at 30 fps. Doesn't even go to 31. ever."
This is exactly what will happen with VSync on, but your rig not pulling 60 FPS.
It has nothing to do with the 60 FPS framerate cap.

My game is running at 30 FPS regardless of me looking up in the sky, on the ground, turning every options to low or simply being in the main menu. One of my friends told me it's a bug with the game's Vsync detection in Fullscreen on certain hardware and that running the game in Windowed and Borderless Mode solves it, and it did for me So if you have this bug try it out. No framerate issue, no screen tearing, just smooth sailing with everything on Bethesda's Ultra quality, and the game looks fabulous.

I was capped at 30 with v-sync turned off.

I have a 144Hz monitor with a GTX 970 FTW.

The only way I could get above 30 fps was to disable the cap.