i have my i3 at 4,0ghz using a Cooler Master Hyper 212+.. It costs around 30$ on amazon and newegg.
My temps are never over 60 and vcore is set to 1.29
On stock voltage and stock cooling i was able to get 3.4ghz (maybe 3.5 depending on motherboard) and temp at 100% load was 65.
Well as i have said i won't be getting a coolermaster 212 plus for core i3(I have it on core i5 750 and it works great) and i can get 4.00ghz stable on 1.224v ,but temps reach to 68'c on stock heatsink.