Rather than encapsulate everything into a performance summary and move on, we'll make a brief tour through our gaming benchmarks, so you can see the practical impact of the X4 980's faster frequency.
Yep, we're talking about a frame per second of difference, or sometimes a fraction of that. Our Bad Company 2 test, which involves logging of frame rates during a manual gameplay session, has enough variability that the X4 975 finishes ahead of the X4 980 in the overall average. At the end of the day, the difference between these two processors is imperceptible in today's games. The only good news here is that both of them can run these games at more-than-acceptable frame rates.
Of course, for gaming, the $117 Core i3-2100 is arguably faster than either of them.