My philosophy is to get the best cooler I can for overclocking, but unfortunately there are problems with the availability of good 1156 coolers. Check out the most recent marathon builds by Toms, IIRC they used the stock cooler with their $1300 build and got a good overclock with it. One ploy they used was to undervolt the CPU to reduce heat output. Also every chip is different and there is some luck of the draw involved, but you might read the article, see what they did, and take your chances.