In short: no it's not worth it. If you've only got a heatsink, stick a 486 fan on top. If you can't spare the PCI slot or you want better cooling, get that Tennmax stealth cooler. And get back to playing games and stop trying to overclock another 0.3fps out of your computer
Thanx all its not that im trying to get more out of my card its got a 486 fan on it.Its the fact i cant put my case on due to the heat in computer.My temp in atx case is to hot for my taste and it seems no matter how i try to cool its still to hot.trying to get it cooler is kinda a pain,power fan is reversed,got a big fan inside front,486 on 550,and one 486 facing out at top of case.My case seems to always be hot even at non overclocked speed.looking into a peltier for cpu.I hear the good ones like step therm dont make to much more heat than standard ones.Anyway my case is still off and i dont like it!