They make some pretty low-priced medium range cpu heatsinks now that are a fair bit better than stock, which is not too bad in its own right. I got the Thermalright MMT9775, which has copper heatpipes and a 92mm fan for $C25, which is only about $US20. Arctic Freezer 7 is near that price also. Not a big expenditure for the comfort of lowering cpu temps, especially if o/c ing. With the Thermalright my cpu has a fairly high 50C idle (E6300 @ 480FSB - 1.34v), but under load the temps only go up to 56C max. With the stock cooler the load temps will be much higher than idle. I would say the stock cooler is good for about 350FSB with the E6300, perhaps the E4300 will run hotter due to the larger o/c.