if you bought a new cpu or an old one, try checking the website, say intel.com or amd.com, look for your cpu and its specifications, specially the max operating temperature.
if they say that ur cpu can operate at this range of temperature, then better believe them. but its best practice to have good cooling. if the room is hot, there no use placing an intake fan, cuz it will make matters worst. room is full of hot air, then an intake fan will just add heat inside ur case. just an exhaust fan will do. hot air tends to go up or escape wherever they can, help them by placing an exhaust fan, i recommend the one that is place on pci slot, or a slot fan. even only one will do.
also, u also have to consider your other hardware, except for the cpu. you also need to tend to your hard drive and video card. go to Arctech for some products that will help you cool these hardwares down. you may also need to get a new heatsink for your motherboard's chipset.
the next thing to worry about is the monitor, dont let it get too hot.
if you dont have some budget for cooling solutions, just open the case when your doing something heavy on your rig, like playing a graphic intensive game, or editing a video.
lastly, if you really dont need it, dont overclock your pc.