Would 450w be enough to run a Radeon HD 7850 1GB

[brinks]

You can try overclocking your computer or maybe turn off programs running in the background.

 

[PP Mguire]

Is there anything else that can increase my fps while being somewhat on a budget, Thanks for the help.

Overclocking if you want to take the risk (I don't suggest OCing your CPU unless you have aftermarket cooling and a full understanding of how to do it),
Turning off ALL background processes when you jump into a game (AV, messenger programs, browsers, everything),
or save up more money to get a better upgrade.

Ultimately, the more powerful the GPU the more FPS you will gain. That said, a more powerful CPU will give slight gains in performance depending on what game it is and how powerful the GPU is.

 

[TheRoo]

Newegg.com - SeaSonic M12II 520 Bronze 520W ATX12V v2.3 / EPS 12V v2.91 SLI Ready 80 PLUS BRONZE Certified Modular Active PFC Power Supply

I couldn't suggest a better PSU.
He nailed it on the head with that choice.