This PC can handle better games ?

[AnswerFTW]

What is +12V ?

 

[Muffin Man]

you should be able to find some info in here, it's lengthy but thorough.
http://www.techist.com/forums/f75/read-first-updated-power-supply-guide-221773/

 

[AnswerFTW]

Could you recommend what power supply i should buy? (not very expensive)

 

[AnswerFTW]

My current power supply is 400W

220V 50Hz 4~

 

[MindoverMaster]

You could get a Antec Earthwatts 500W for $70