Framerate Issues With Street Fighter x Tekken (STEAM)

First off, apologies if this is the wrong thread. My knowledge of computers is limited so I don't even know where to categorize this.

So, the specifics:

Game: Street Fighter x Tekken (Running on STEAM)
Machine: Intel Core i7 2.3GHZ, 8GB RAM, GeForce GT 630M 1GB Video Card.
OS: Win 7 64-bit

So, I bought the game in question in February. When I first played it it ran at 78FPS on maximum settings. I was THRILLED. Played it for about 2 hours in total. In March I tried to play it once and noticed slow down. I was now getting 55FPS! The game is programmed to run at 60 so anything less than that and it lags.

My knowledge of computers is limited. Can you kind folks please brainstorm why this would even happen? Feel free to ask me ANY questions regarding anything about my laptop. I hope I have provided sufficient information.

a few reasons for this : 1. are you using higher resolution, higher res will reduce fps 2.is there another graphic intensive process running at the same time as the game 3.the hard drive might get fragmented, try defragmentation

Hey man. I believe I'm running it at 1600x900. There is no other intensive process running to my knowledge! Is there any reason why it would first work brilliantly and then shit the bed randomly? Thank you for your time.

in vga card sense, the only thing that may cause the slowdown is when it's getting hotter than normal thus automatically slowed down to cool off, but this is unlikely to happen if all fans are working well. if possible, use gpu monitoring software like gpu-z to check vga status(core usage, memory, temperature etc.) while playing the game. this will reveal what's the one not working normally like before.