Closer Look at Nvidia GeForce GTX 680 2GB Graphics Card
The technical specifications of the new Nvidia GeForce GTX 680 are summed up in the following table and compared side by side against predecessors – GeForce GTX 580 and AMD Radeon HD 7970:
Design and Functionality
The reference Nvidia GeForce GTX 680 doesn’t look much. It has a dual-slot design with a plastic casing and a centrifugal fan in its back. The reverse side of the device is exposed:
The PCB is 254 millimeters long, the cooler casing being no longer than it. There are large letters “GEFORCE GTX” running along the edge of the device. An Nvidia logo can be found in the bottom right of the face side. The GTX 680 will mostly ship in this form, perhaps with different labels and decorations, for the time being. Non-reference versions are likely to come about no sooner than in a couple of months.
According to the official specs, the Nvidia GeForce GTX 680 is equipped with two dual-link DVI ports, one HDMI version 1.4a, and one DisplayPort version 1.2:
If you take a closer look, you can see that the top DVI connector is DVI-D whereas the bottom one is DVI-I. Besides the numerous connectors, there is also a vent grid in the card’s mounting bracket. The air exhausted out of it was very hot during our lengthy tests, by the way.
Quite expectedly, the card has two MIO connectors for SLI configurations in the top part of the PCB.
The two 6-pin power connectors are placed one above another in such a way that the cable locks are both inside. But since the connectors are rather far from each other, it is quite easy to plug and unplug power cables. The card is specified to have a peak power draw of 195 watts, which is 55 and 49 watts less than required by the AMD Radeon HD 7970 and GeForce GTX 580, respectively.
The plastic casing is secured with screws along the graphics card’s perimeter. Below it we can see a GPU heatsink and a metallic plate with centrifugal fan that covers almost the entire face side of the PCB.
Here is the PCB with that plate removed:
We can see a 4+2 power system here. Interestingly, the fifth phase is not installed, just like yet another 6-pin power connector:
It looks like Nvidia developed this PCB with a higher-performance solution in mind. We don’t think that’s just a cost-cutting measure, especially at the moment of the product’s announcement.
And, finally, here is the open-die 28nm GK104 processor. It is a mere 294 sq. mm large:
The GPU of our card is revision A2 and was manufactured on the third week of this year. Its default clock rate in 3D mode is 1006 MHz at a voltage of 1.15 volts but it can get as high as 1124 MHz with the GPU Boost feature. In 2D applications the GPU frequency is lowered to 324 MHz at a voltage of 0.987 volts. We’ve already discussed the new GPU’s specs above, though.
There are eight GDDR5 memory chips on the face side of the PCB. They are manufactured by Hynix Semiconductor and labeled H5GQ2H24MFR R0C:
The chips are clocked at 6008 MHz at a voltage of 1.6 volts. This is the fastest memory among all serially produced graphics cards. However, the memory bus is 256 bits wide, so the memory bandwidth is only 192.26 GB/s which is equivalent to that of the GeForce GTX 580 with its 384-bit memory bus and 71.74 GB/s lower than the memory bandwidth of the AMD Radeon HD 7970 (5500 MHz and 384 bits). The GeForce GTX 680 drops its memory clock rate to 648 effective MHz in 2D applications.
3 days before the official launch of the new GeForce GTX 680 a new GPU-Z utility version 0.6.0 came out. It is already fully familiar with specifications of the new product:
The recommended retail price of the Nvidia GeForce GTX 680 is set at $499, which is $50 cheaper than AMD Radeon HD 7970 and $50 more expensive than JHD 7950. Soon we are going to find out what the performance ranking is going to look like.