Bug/Issue Extremely low FPS after a few minutes of playing

When I first installed the game, it ran more or less fine, having some drops in the FPS from time to time but nothing too terrible. After around 20 hours of playing though, the game started slowing down to a crawl that makes it basically unplayable. It doesn't matter where my character is or the weather, though of course rain and such makes it even worse.

Whenever I start Starbound now, the first one or two minutes run fine, and then a massive drop in FPS happens. Sometimes it increases for at most a few seconds before plummeting again. I thought maybe I had installed one too many mods, but even after uninstalling every single mod, uninstalling the game, and even deleting the Starbound folder in the Steam directory, nothing changed; a fresh install will still have the exact same problem. I tried all FPS booster mods, and while that makes the game playable for a while longer, it eventually has the FPS drop regardless.

To make matters even better, after I tried updating my graphic card drivers to see if it'd help, now the game has some horrible screen tearing as well, which happens regardless of whether or not vsync is on.

In case it matters, this started exactly around the time I had my first character have the second upgrade to the ship, after having hired a red chemist, and I was visiting a jungle planet orbiting a radioactive star.

Anyone has any idea of what could have caused it? Or what I could do to fix it?

My system specs:
Intel Core i7-363QM 2.40 GHz, 8 GB RAM, my graphic card is a NVIDIA GeForce GT 630M

EDIT: Alright, so. I tried using my integrated graphic card (Intel HD Graphics 4000) to see what would happen. The good news is that the game runs incredibly smooth, and at least in around 10 minutes of playing there were no massive FPS loss. The bad news is that there is constant, horrifyingly large screen tearing. Like, huge white bands flickering for half a second, basically everytime I move.

If I could just... fix... that tearing......

EDIT 2: Alright.... alright, so. I was playing on borderless window and that was the reason behind the tearing.
So, uh.
If you're having a problem similar to mine, just ues your integrated graphics card, play on windowed mode and disable the bordless window option.
Jesus Christ.
Sorry, you guys can lock this thread now.