ive got an msi 9800 pro,the one with the big heatsink.i can currently overclock the core to 430,and the mem to 365,no artifacts.if i remove it and add arctic silver 5 to the core and mem,would i be able to overclock it more?if not more,would i run the card cooler?is it worth going through this with a stock heatsink.any idea or opinions is wanted.