Well I tried to mine with my PC too. But it puts too much stress on PC I don't recommend it not that it's not profitable but because it can ruin your PC that kinda happened to me
. In any case you can try do it but don't leave your computer up for too long and don't run it on full capacity. At least that's my opinion in this.
8500 MHash/s is not high at all. You will hardly find a block. Better look for others alternatives than minning