which cpu is better?

For what uses? The A4 is 10x better for watching movies and very light gaming, but the Pentium is a lot stronger in processing power.

If I wanted HTPC media center, I would go with the A4, if I just wanted a cheap basic desktop for basic uses, I would go with the Pentium.

and then honestly, I wouldn't get either one. There are other better Pentiums in the same price range that would be a better buy, and usually an A6 can be found for around the same price as the A4.