Intel Ivy Bridge processors are pretty different in terms of overclocking as compared to their predecessor; Sandy Bridge. In a Sandy Bridge system, CPU itself or motherboard would become a bottleneck and one of these could be the major reason holding a system getting overclocked further; cooling would rarely become an issue. Ivy Bridge has changed the things a lot. It runs considerably hot even at the clocks that were like a walk in a park for Sandy Bridge. Maximum most Ivy Bridge systems can achieve on air is around 4.6 – 4.8 GHz. It can be pushed further but increasing heat becomes the holding factor; CPU or motherboards rarely reach their limit.
This is why we are changing our overclocking methodology a bit. With Sandy Bridge, we used to push the processor as far as it can go on the given motherboard and air cooling and we’ve seen it passing 5 GHz all the time. With Ivy Bridge, we’ve selected a reasonable clock speed of 4.7 GHz and we’ll push our Intel Core i7-3770K to 4.7 GHz with every motherboard we’ll test. Now the question that must be bugging your mind is that how readers will be able to know which motherboard is better at overclocking when all of them will be pushed to same frequency and the answer is CPU voltage or vCore will be the deciding factor.
Motherboard having a better and efficient power delivery system will essentially need less vCore to achieve 4.7 GHz while others will need higher voltage. It’s not a perfect way to check overclock-ability of a motherboard but it surely gives a fair idea about it.
With ASRock Z77 Extreme9, we were able to push our Core i7-3770K to 4.7 GHz without much hit and trial. All we needed to adjust was voltage, load line calibration, internal PLL overvoltage and power limits. We needed around 1.25v for CPU to get the 4.7 GHz stable. Load line calibration level was set to 1 and internal PLL overvoltage was enabled. We tested the stability by running Prime 95 for around 1 hour and it was all good.
Same processor took around 1.27v to reach 4.7 GHz with ASRock Fatal1ty Z77 Professional.
Let’s have a look that what kind of performance gain do we get with the Intel Core i7-3770K overclocked to 4.7 GHz.
x264 HD Benchmark:
Alien Vs. Predator:
Resident Evil 5:
Overclocked Power Consumption:
Power consumption gets a huge hit when CPU is overclocked.