Can my PC run it?

Solution
Yes, a GT640 will work on your 300w power supply, but if you're going to spend $80-$90 I would highly recommend spending another $20 to get a GTX750. It will also run on your power supply and it's over twice as fast and a newer model of card.
Yes, a GT640 will work on your 300w power supply, but if you're going to spend $80-$90 I would highly recommend spending another $20 to get a GTX750. It will also run on your power supply and it's over twice as fast and a newer model of card.
 
Solution