Hello.
I would recommend to you to use MSI Afterburner. It is fairly easy to use. Also get MSI Kumbustor. This will have no effect on your CPU or your motherboard, just on the Graphics card.
Start with the "Core Clock" Adjust the speed up 25mhz, then run a test for about 3 minutes in Kumbustor and watch for any graphical anomalies. Continue increasing speed until you get graphical anomalies, then reduce it by 10mhz until anomalies vanish.
Next do the same thing with the Memory Clock in the exact same way. Unfortunately your results will be a little worse because of your choice of card. The GT630, while it is a decent little card, will never be able to use 4GB of RAM. The result of having so much extra RAM is an increase to the cost of your GPU, increased power usage, and increased heat production. As a result of the increased heat your RAM will likely not be able to able to reach as high of a speed as a 2GB or 1GB version of the same card, giving worse performance. Also because one of the many chips on the board may not be able to reach as high as the others and result in poor overclocking performance.
Overall though I think you will get good results. My laptop has a GT620m which uses the same chip. I was able to push it from 625Mhz to 788Mhz on the Core, and from 900 to 1050 on the RAM and got good improvement from it. While all chips are different, I think you will be able to also get good results.