This system is for my Nephew and he love to play games, from his point of view, he would love to play ALL LATEST games, but I know that with 20k budget I might not able to buy him a PC that allow to play all games.
@Emperor, will your nephew be mainly using photoshop or gaming? If its gaming, you will be better off with a G2020 + entry level GPU (for the same price of an i3). After 2 years when you do change your GPU, I highly doubt your nephew will complain that he is getting 2 fps less with his G2xxx, but he will be complaining for these 2 years that his i3's HD 2500 graphics is rubbish for gaming.for photo shop, anything below an i3 is simply crap. If you just want something cheap, get G220 and regret later or invest 2k more in a much much better processor.
Add in the fact that modern versions of Photoshop are showing huge boosts from GPU assisted acceleration, and I'm still wondering how the i3 offers any value for your situation.