Pushpin? On mine, when I put on the stock cooler, and my old 939 rig was the same, there were 2 brackets on the heatsink. There should be 2 almost like plastic square teeth on plastic piece where your heatsink is supposed to mount to the mobo. Then on your heastink, there should be a lever on one side. Loosen the lever as much as it will go, and the holes on the bar of the heatsink should fit over the plastic part on your board, then pull the lever down to tighten it. If your heatsink really is a pushpin, are you sure you didn't get the wrong one when you ordered? Because I think Intel's stuff is pushpin style, but not AMD's newer stuff usually. If you can't get it on, if you bought the chip as retail, use the stock heatsink, should be adequate if not overclocking. That's what I'm running my 5200 x2 on and it runs fine. Also, when you put the thermal grease on, don't use too much, I would say use about a small drop, and spread it on the top of the chip. I personally just ground myself and use my finger. Though a card works ok too.