The memory frequency doesn't differ from the reference card's: 7012 MHz in 3D applications and 648 MHz in 2D applications. Thus, the Palit GeForce GTX 770 JetStream has the following specs:
The GPU of our sample of the Palit card has an ASIC quality of 82.5%.
The card's cooling system consists of three main parts: an aluminum heatsink with five 6mm copper heat pipes responsible for the GPU, a steel heat-spreading plate on the memory chips and power system components, and a plastic casing with fans:
The heatsink has two sections. The bigger section is pierced by the two middle pipes and the smaller, by the remaining three.
The heat pipes seem to be fastened to the cooler’s copper base with thermal glue. The heatsink fins are simply press-fitted on the pipes, which may have a negative effect on the overall performance of the cooler.
The heat-spreading plate contacts with graphics card components by means of thermal pads and, like the main heatsink, is cooled by the fans.
There are two types of fans here, both manufactured by Power Logic. The central 92mm fan has translucent blades and blue highlighting. The other two fans are 80 mm in diameter and simpler in design:
The speed of the main fan is PWM-regulated. Judging by the connection type, the other two fans are regulated by changing their voltage. We don’t know which exactly fan is used for monitoring, but the card's monitoring data indicate that the fan speed varies from 780 to 2730 RPM.
To check out the cards temperatures we used five runs of the pretty resource-hungry Aliens vs. Predator (2010) benchmark at the highest visual quality settings, at a resolution of 2560x1440 pixels, and with 16x anisotropic filtering and MSAA 4x.
We used MSI Afterburner 3.0.0 beta 10 and GPU-Z version 0.7.1 for monitoring of temperatures inside the closed system case, which configuration is discussed in detail in the corresponding chapter of the roundup. All tests were performed at 25°C room temperature.
Now let’s check out the efficiency of the cooler installed on the Palit GeForce GTX 770 JetStream when its fans are regulated automatically:
The peak GPU temperature was 80°C during this test and the fans only accelerated to 1650 RPM. We’ll check out the noise factor shortly but we can already say that the cooler is efficient, considering the pre-overclocked GPU.
At the maximum speed of the three fans, the GPU temperature was 11°C lower at only 69°C.
So we can see that the cooler's performance depends on the speed of its fans.
Checking out the card’s overclocking potential, we managed to increase its GPU and memory clock rates by 60 and 920 MHz, respectively.
The resulting clock rates were 1210/1262/7932 MHz:
The GPU clock rate would peak to 1306 MHz during the temperature test, though:
We can note that the GPU is still no hotter than 80°C thanks to the fans accelerating to 1740 RPM.