Design and Functionality
The reference cooler of the GeForce GTX Titan must have been found commercially advantageous, so Nvidia releases a third product with it already. The single difference is in the model name we can see on the cooler’s casing next to the card’s mounting bracket. It was “Titan” first, then “GTX 780”, and now it is “GTX 770".
Otherwise there are no visual differences save for the lack of memory chips on the reverse side of the PCB. The product series name on the top edge of the card is highlighted, just like on the senior models.
Like the GeForce GTX 780, the new card is equipped with four video outputs: dual-link DVI-I and DVI-D, HDMI 1.4a, and DisplayPort 1.2.
Two MIO connectors for building 2-, 3- or 4-way SLI configurations can be found in the conventional location:
The card has one 8-pin and one 6-pin power connector and is specified to consume up to 230 watts of power. This is 35 watts more than required by the GeForce GTX 680 and 20 watts less than consumed by the GeForce GTX 780. We can see a trend towards higher power consumption as long as GPUs remain on the current manufacturing process.
The PCB resembles the GeForce GTX 780 but partially. There are fewer memory chips here. The power system layout is different.
There are five power phases for the GPU, and one for memory and PLL each.
The power system is managed by an ON Semiconductor NCP 4206 controller.
The 28nm GK104 chip was manufactured in Taiwan on the 46th week of 2012 (mid-November).
The GPU die is 294 sq. mm large, incorporating 3540 million transistors. The GPU is clocked at 1046 MHz and this frequency can be increased to 1085 MHz in boost mode. However, with the Power and Temperature Targets set at their maximums, the GPU clock rate would reach 1136 MHz during our tests, which is much higher than the specified level. In 2D applications the GPU drops its clock rate to 135 MHz while its voltage is lowered from 1.2 to 0.862 volts.
The graphics card carries 2 GB of GDDR5 memory in FCBGA-packaged chips installed on the face side of the PCB. These are Samsung Semiconductor’s K4G20325FD-FC28 components.
According to the manufacturer’s website, this is the fastest GDDR5 memory available from Samsung. It is rated for 7000 MHz, which is indeed the memory frequency of the GeForce GTX 770. In 2D mode the frequency is dropped to 648 MHz. The memory bus is 256 bits wide, as on the GeForce GTX 680, but the higher clock rate ensures higher bandwidth, which is increased by 32.1 GB/s or 17%.
So the Nvidia GeForce GTX 770 has the following specifications:
The ASIC quality of our GPU is 78.6%.