Does the company cooling fan that comes with i7 4790k is enough for just gaming? Or do I need to buy some costly cooler to keep my CPU's temp low? I don't have any plans to overclock it. I just play games. That's it!! Please suggest.
The stock cooling fan is good enough as long as your case has good airflow.
If you do have issues you don't need some costly cooler, the Coolermaster Hyper T2 is usually about $18 and will do the job excellently if you never overclock.