How good is Xp palomino's retail stock heatsink and fan?

Where I live, there's almost dif in price between OEM and retail box. Considering that the latter comes with a free heatsink/fan combo, it looks like a good deal, but I'm not sure how well it works when overclocking the cpu. Also do all retail boxed xp palomino cpus use the same type of hsf combo? If so, the hsf on a 1.6ghz cpu should be sufficient when the cpu is over clocked to 1.8 (if the cpu can handle it in the first place), since both retail 1.6 and 1.8 use the same cooling solution.