Depends entirely on what you're playing and whether or not you use the integrated graphics.
In older 1-2 core games with a discrete card the i3 is better.
In newer multicore optimized games using the integrated graphics, the AMD A8 is better.
RE: Tom's CPU Hierarchy chart...this is old information based on testing with 2-3 titles that don't use all of AMDs cores. Most current releases present very different results. So it depends greatly on which titles you will play, how old they are, and how well optimized they are.