So, in order to keep noise in check while cooling the GTX 780 Ti with a 145MHz factory overclock KFA2 developed an exceptional triple-slot cooler. Let’s see how it performs in the real world.
It is perfectly understandable that the GTX 780 Ti HOF heats up a bit more than the reference GTX 780 Ti, but the good news is that the noise level is roughly the same, even better, despite a high factory overclock. The GTX 780 Ti HOF cooler is relatively quiet in 3D mode and noise is simply not an issue. While idling the card is practically silent. In idle we measured 28 to 30 degrees Celsius.
The fan management is excellent and the two 90mm fans won’t surprise you with sudden RPM changes. The maximum GPU temperature is allowed to reach up to 95 degrees Celsius and the thermal threshold is set by Nvidia at 82 degrees Celsius, but you do not have to worry with the GTX 780 Ti HOF. Under load the GPU temperature can hit 73 degrees Celsius in some applications, but we usually measured somewhat lower temperatures.
Note that we tested the GTX 780 Ti HOF card inside the Cosmos II Ultra Tower with a lot of airflow. The HOF cooler, like any other high-performance cooler, loses its edge in a low airflow environment. To see how well it copes in a compact chassis, we tried using it in an EVGA Hadron Air chassis. The miniature chassis was not a good fit for the HOF, as the temperature climbed to 82 degrees Celsius. However, in the big Cosmos II chassis the cooler got a chance to shine and deliver excellent performance.
The following graphs show how well the cooler performs compared to the reference unit. The first graph shows HOF results at 1020MHz, with Boost clocks going up to 1111MHz. The card heats up to 71 degrees.
KFA2 GTX 780 Ti HOF
Now let's take a look at the reference GTX 780 Ti. The GPU heats up to 75 degrees at 875MHz base and 1020MHz Boost clocks. The noise levels are about the same, but keep in mind that the HOF operates on much higher clocks.
Nvidia GTX 780 Ti reference clock
We tried a different test to check out the reference cooler. We sped up the fan to maximum RPM and increased the GPU clock to 1020MHz. The Boost clock hit 1165MHz, but it did not stay there for long. Although there reference card's peak clock was somewhat higher, its average Boost clock stood at 1110MHz, on par with the HOF.
The reference cooler was operating at 4200RPM and generating quite a bit of noise. The GPU temperature was reduced to 67 degrees, as shown in the following graph. We got roughly the same temperatures on the HOF (with the fans at maximum RPM), but when its cooler is maxed out, it is significantly quieter than the reference Nvidia cooler.
Nvidia GTX 780 Ti overclocked (base GPU clock at 1020MHz, fan at MAX RPM)
Using HOF's Hyper Boost mode delivered a steady 1111MHz Boost clock. The next graph shows HOF numbers when its fans are running at max RPM. PrecisionX did not display the exact RPM, as it works in percentage points. However when the fan speed is set to maximum via PrecisionX, it is about the same as the Hyper Boost speed.
When using HOF's Hyper Boost, the PrecisionX did not display the exact RPM in percentage points