Processor at 4600 MHz with Higher Voltage
Now we up the ante. Understand that 1.30V and higher voltages are the levels where Haswell processors get into serious problems due to the aforementioned heat-spreader versus TIM design applied solution from Intel. We now set the Core i7 4790K @ 4600 MHz and apply 1.30 volts on the CPU while loading it with 100% stress for wPrime to run on all available CPU threads three times. Below, you can see the IDLE results with the Core i7 clocked at 4790K @ 4600 GHz with 1.30 volts on the CPU. Again, the results are the IDLE temperatures thus you are on your desktop doing pretty much nothing.
The temps normally rise above and beyond 90 Degrees C for a lot of heatpipe based coolers, which is a definitive no-go. As you can see, we have dangerous temperatures for most coolers. LCS class coolers perform far better here.
To advance on overclocking to see where our thermal threshold (the point of no return) is we tweak in four stages where we up the core voltage from 1.30v upwards to a more (unrealistic) 1.40v. At 1.4 volts any heat pipe cooler would fail but with LCS you can stay just under or at that 80 degrees C marker (which I can only advise for a short period of time).
Performance relative to temperatures and DBA levels based on profile mode settings
In this last chart, we will apply a hefty 1.35 Volts overclock on the CPU and put it under load. We now change the fan profile settings and look at the behaviouristics in terms of temperatures and DBa levels.
Here I tweaked the CPU to 4600 MHz on all cores and fired off 1.35 Volts. Silent and Balanced mode still offers enough performance while remaining silent. Extreme mode is best, but very noisy once the coolant heats up.
That Zero RPM mode, the fans do not kick in until the LCS coolant reaches 40 Degrees C. That in fact might be a too high value as by then your proc will already have risen towards or over 80~90Degrees or higher before that coolant flow reached 40 Degrees C. Be very careful with that setting. It would be nice if Corsair could implement a configurable or lower coolant temp threshold, I'd prefer the fan kick in value at 35 Degrees C coolant temperature as opposed to 40 Degrees C.