Will Hardware upgrade solve low FPS problems?

My FPS has drastically reduced to below 30 while playing DOTA 2 on its lowest settings. I decided that the best solution would be to upgrade the hardware. I did that and now I am facing a huge problem since the hardware has reduced the performance of the game further. I have an Intel Core i7-2670QM CPU with 2.20 GHz, 4GB RAM DDR3, Windows 7 64 bit and an NVIDIA GeForce GTX 560M graphics card computer. Your help will be very much appreciated.
