This is a now decision as you will benefit from any better cooling from the git. i suggest that only you know what you plan to do, OC or not. Gaming and basic operation will demand you have at the mimium and anytime you go above that, have better. I mention this as once you play and get by you'll try to get the best from your system as it is and that may do but any stress or over-temp situation can quickly degrade the components and all the the devices present until the weakest link is found. Thus, I suggest you build the best system you can and get what's needed for now and not later. If later is a short time, maybe OK then. You take from there what's best for you. A stock cpu fan does well for stock situations but you already suggest gaming, OC and possible movie watching(prolonged activity) and that means you want a decent system to start off with. Of course, if you can cool the entire PC with additional or yet other cooling methods then take that into account.
tada -----Willy 
I am buying a new computer very soon. I don't intend to overclock...at this time. Some gaming and movie watching. It IS my entertainment centre. Is it worth buying a Noctua 12 performance CPU cooler? I saw a video on Youtube by an experienced builder who said the stock Intel fan will outlast any other fan and anything else is a waste of money. Is this true? Regards Lucid Oldie
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