CPU Versus APU?

APU is a term AMD gave their CPU that also has a graphics core inside the CPU chip. Llano is AMD's 1st APU and it came out last year. Llano APU are socket FM1 so you need a socket FM1 motherboard. The integrated graphics core can be Crossfired with up to a Radeon HD 6670 for combined better performance. Inserting a more powerful Radeon HD card or inserting a nVidia card will automatically disable Llano's integrated graphics core.

Intel's version of the APU is the Sandy Bridge series of Core i3/i5/i7 CPUs and they are also released last year. This is the 2nd generation of Core i3/i5/i7 CPU and they have either the Intel HD 2000 or Intel HD 3000 graphics core integrated into the CPU chip. Intel simply calls them CPUs. Sandy Bridge CPUs are socket 1155 so that's the socket the motherboard must have as well. The 1st generation of Core i3/i5/i7 CPUs were socket 1156 and it uses a different motherboard; socket 1156. Inserting any AMD or nVidia graphics card will disable the Intel HD 2000/3000 graphics core.

Integrated graphics are still relatively weak compared to discrete graphic cards. The Intel HD 3000 is basically equal to the Radeon HD 5450 in terms of performance. I think the most powerful graphics core is called the Radeon HD 6620G and is found in the Llano A8 series. On it's own, the HD 6620G is probably almost equal to a Radeon HD 5570. The performance of those integrated core are very weak when compared to your average $125 - $150 video card.