How well does she over clock? That will determine the real value. Or have you oc'd it?
The better they OC and the lower the voltage necessary to pull it off the more you will get for your chip.
The 2500k has to be one of the best chips intel has put out in recent years so I am sure you will have no trouble finding a buyer.
I think I'm one of the lucky ones with mine. -0.08 voltage at 4.5ghz and less than 65'c at full load with a h60(coolit eco II).