Hp g62 core i3
Under Warranty and laptop is hanging (lagging)

I bought the laptop in august for educational purpose and it's april now and under warrenty. It keeps on hanging in the middle of applications which at first i thought might be because of the internet's speed, but now I'm sure it's not .. It's really getting up my nerves and is very annoying and it's giving me delays with the dealines I have to meet. What should I do in regards so that it gets exchanged for a new laptop or to refund my money. Your help would really mean alot to me.

Thanks

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