I suppose that at some point in time I should have tested the stock cooler that came with my i7, but I never use those coolers. I think that only once I have used a stock cooler, just to see how poorly it performed. I’ve read of stock idle temps in the 40s and stock load temps in the 70s or higher, so I don’t bother.
I compared the Evercool Buffalo with the Kingwin XT-1264, to give some kind of reference point to see how the Buffalo performs. This is not a fair comparison for the Buffalo, as not only is the Kingwin cooler much larger, it is a real performer, especially for the price, so do not consider this a shoot-out between the two coolers. I suspect that the Buffalo’s performance will be far below that of the Kingwin cooler. that costs over 1/3rd more than the Buffalo.
I monitored CPU temperatures with Easy Tune 6, Gigabyte’s software overclocking and hardware monitoring utility. Idle temperatures were taken with the system sitting idle for 30 minutes, load temperatures were taken with the CPU running at 100% load for 30 minutes.
CPU load was attained by using Prime95 version 25.8 64-bit. The “Torture Test” of this latest version of Prime95 not only utilizes all four cores, it also utilizes the i7′s four virtual cores, maxing out all 8 threads. I used the “small FFT” setting as I wanted to stress only the CPU and not the memory.
First I tested temperatures at stock clock of 2.66gHz.
Though an aftermarket CPU cooler’s story is never told at stock clock, I recommend using an aftermarket cooler even for a rig that will never be overclocked. The Buffalo is a very economical cooler, and keeping the stock clock load temp just over 40C would make it an excellent replacement for the i7′s stock cooler in a stock clock situation.
Next, I overclocked the i7 to 3.86gHz. This isn’t my high overclock for this processor, which is just over 4gHz, but is a very healthy overclock which I felt would push the Buffalo to its limits, if not beyond. This overclock requires cranking up the i7′s Vcore and QPI voltage, which really heats things up.
My i7 920 shuts itself down when the core temperature reaches 90C. I have only reached that temperature once, when a push pin wasn’t properly seated. My overclock was just too much for the Buffalo, I watched the temperature steadily climb to 89C and all went black. The cooler was seated properly, the thermal compound was properly spread with no bubbles. It just isn’t enough cooler for a high overclock, which is quite alright for a cooler costing 1/4 the cost of an upper end air cooler.
So I cranked the Base Clock down a lot, even down as far as 3.0gHz but the temp still reached 90C. Finally I lowered the Vcore and QPI voltage and that made the difference. I settled on a 2.92gHz overclock, which makes the i7 920 perform at the speed of an i7 940, the next processor in the series. That is an overclock that many beginning overclockers are satisfied with, including myself when I began overclocking. At this 10% overclock, the Buffalo kept the i7 at 48C.