First hello to everyone! Second, I have a few doubts. I am going to buy a new PC like in the next week or so and I just want to spend as little money as possible, but be able to play latest games. I spotted a nice good pc: chieftec case and 500w Chieftec psu, 4gb 1600mhz ram and 500gb seagate hdd, but the cpu was AMD APU A4 which is a 2.5 ghz dual core and it costs just below 400$. So would the cpu handle the newest games if I throw in a HD 6770 or a HD 7750 gpu, or should I just look for something more expensive like AMD quad-core 631? Of cource 631 would be much better, but would it be enough with the a4?
Not worth going dual core apu at all, for any reason it isn't a good idea. Weak performance, awful power consumption for the performance, and is already getting to be weak for daily use like web browsing ect. Dual cores at such low clocks are terrible for gaming and on the intel side it is a little better especially for games that are still stuck in the stone ages that only use one thread. Fore everything else intel dual cores are a little anemic in the long run but for now are enough to get by.
The whole idea of an APU is to actually use the built in graphics. You can boost those with a 6670 card, but that's about the highest card that works in crossfire with an APU. While this is not the worst solution for low end graphics at all, it's still paired with a slow CPU.
If you want to throw in a dedicated card anyway, get a better CPU.
Tom's hardware already has a bench out for the upcoming Trinity APUs, but they're not available to us builders yet, but initial impressions look like they're going to be pretty promising improvement over Bulldozer. I'd sit tight a few months and allow you to save up some more money.