|Intel Core-i3/i5/i7 LGA1156 Overclocking Guide|
|Articles - Featured Guides|
|Written by Servando Silva|
|Tuesday, 24 August 2010|
Page 9 of 10
Overclock vs TemperaturesHeat is one of the main concerns when overclocking. Some people think they could fry their CPU because of the heat, and that scares them. However, this is far from reality. CPUs and motherboards are so protected that it is almost impossible to burn a CPU by heating it that much. It would be easier to fry your CPU by short circuiting or adding extreme voltage values, but heat isn't normally a problem as components tend to shut down when passing off their limits. However, even if heat isn't that dangerous, it's key for higher and stable overclocks, and that's why Benchmark Reviews covers a lot of CPU heatsinks in our articles. In my tests, I used Noctua's NH-D14 heatsink paired with 2 x NF-P14 140mm fans. Most people won't have this kind of cooling, but Prolimatech Megahalems or Thermalright Venomous-X should be able to get similar results for the Core i3/Core i5 processors. Anyway, if you're really aiming at maximum frequencies, you'll need to buy a decent heatsink. If you're stucked with Intel's stock cooler or something similar, chances are that you won't be able to stabilize anything above 1.3 volts. In this case, I included full load (Prime95 Blend Test) results, because idle results are too low to become a concern. The Core i7 860 idles somewhere between 25-35 degrees (depending on OC), while the Core i3 and Core i5 CPUs didn't pass 30 degrees in idle mode. Not even overclocked.
You've got to love that Core i3 530 CPU. This little chip has a TDP of 73 watts, and it consumes so little energy that it remains at 40 degrees at full load. That's something impressive. Overclocking it to 3.9GHz only increased this result by 1 degree. When I increased vCore to 1.3v, the temperature raised 5 degrees, and finally ended at 55 Celsius at full load with 1.5 volts. If you're using this CPU and you have a smaller heatsink you should be able to keep temperatures far below the limit (75C-80C) since we've got a 25 degrees gap before reaching it with this huge heatsink.
The Core i5 655K reached higher temps, usually 5-7 degrees higher than the Core i3, and that sounds fair considering it overclocks a little bit more. The interesting part is the small 2 degrees increment at stock voltage when overclocked to 4050MHz. I think running a CPU at 4GHz while having 47 degrees at full load is like being in heaven, and you'll be getting back what you paid for it. Finally, the Core i7 860 being a 4 cores processor is much hotter. It almost reached 60 degrees at full load with stock voltages (something we didn't reach with 1.5v on the rest of the CPUs), and kept rising until reaching 75 degrees with 1.5v, which basically is touching the limits of acceptable temperatures. Since you'll probably run it at 1.3v only (to reach 4200MHz) chances are that you'll keep your temps below 70 degrees. If you think that's still too much, then you'll have to live with stock voltage overclock, especially if your heatsink isn't good enough to handle those quantities of heat.