umm, first off, is this comp really old? and second, do you know for sure that its getting hot in there? What are the temps? Dont just replace stuff for no reason. If its old then its fine, dont buy more stuff for it. Most prebuilt comps are cooled fine. Unless their loud.
i've had it about a year or more, and the room its in gets about 90 degrees plus in the summer and its getting hot where i am, plus i dont trust that heat sink on my cpu because its just a heat sink. i want to put the one with a fan and heatsink to keep it cool. and the lights on the fan looks nice to lol.
It's not backwards, it's just a BTX. My Dell is BTX and it actually runs really cool, when I lived in Phoenix my room would get above 80 degrees on some days during the heat of the day, this is the first computer I've had that didn't slow down during those conditions. My old HP, and emachines computers would slow down really slow during those times, and I would have to shut them off until things cooled down.