The graphics card doesn't make a CPU faster. The i5 regardless of graphics card is faster than the 6300.
It does if it was bottlenecking your CPU previously. The point you are trying to make is that an i5 with a HD5450 is better than an FX 6300 with a HD7850. So no it is not faster regardless of GPU.
And to answer Op's question, yes the i5 is better than the 6300. To compete with the i5 you need to compare it to the FX 8300 series.