Build PC or Get Tablet for 18th Birthday?

Hello,

I need advice on whether to build a PC or get a Samsung Galaxy Note 10.1 tablet for my 18th birthday. I am in a very important year in school so I don't want to get distracted playing games this year. However next year I will want to play games. I was thinking that if I built a PC this year I could spend a bit more on a thunderbolt motherboard and use Intel 4000 graphics in an i5 3570k. Then, rather than buying a good graphics card this year and not get much use out of it, wait until next year and buy one then.
Or I could get a Samsung Galaxy Note 10.1, which would be more for portability and for media consumption than anything else. I also like the idea of the stylus for taking notes, annotating PDF's and sketching. The only thing is tablets aren't really upgradable and can become obsolete quickly as a result.
I have a 2 year old netbook at the moment which is my main computer so a tablet wouldn't really be a massive upgrade, but a PC would. I'm just wary of the amount of usage I would get out of the PC this year compared to the tablet, but tablets are becoming better and better each year so this tablet could be obsolete in a year or two.
I would like your opinions on which would be better for me to get this year (if any!)
Thanks in advance for any replies!