Question about ballast and HPS

Can I take a 150w ballast and put a 250w lamp in to it? Because my friend had a spare bulb sitting around and gave it to me... if not do you know of any cheap ballast sites... or a good store to buy it from? thanks guys!

Thats a pretty dumb question don't you think? The globe will not ignite, as the ballast cannot supply the power required to ignite the gas

i dont know man... i mean who knows maybe it would just take longer for it to burn bright but once its hot maybe it could keep it up... im not an expert... does anyone know of a good site or place to buy one?