The GeForce GTX 680 graphics card on the test bench today is a dual-slot single GPU video card that measures in at 10-inches in length, which is half an inch shorter than the GeForce GTX 580! NIVIDIA gave the GeForce GTX 680 fan shroud more of an angled shape which gives it the appearance it was designed by military engineers trying to reduce the radar cross-section and minimize straight lines.
Turning the NVIDIA GeForce GTX 680 over there is not much of interest as none of the memory chips or major components are located on the backside of the PCB. We used a pair of dial calipers and found the mounting holes around the GPU are spaced 58mm apart. This is good news for those that like to use aftermarket GPU coolers as this is a fairly common size.
One item on the back of the PCB that did warrant further investigation was a small ‘daughter’ PCB soldered to the main PCB for the PWM controller (RT8800A Datasheet). Our GeForce GTX 680 reference card used a Richtek Technology RT8800A General Purpose 3-Phase PWM Controller for High-Density Power Supply. We were told that since the power control on video cards is getting pretty advanced that NVIDIA wanted an easy way to change controllers if needed. By designing a secondary PCB with a standard foot print, we assume that NVIDIA can change controller brands quickly without a complete PCB change. This is also great if prices on a component go up, they can switch over to another brand or model and not be tied to just one company or component.
The NVIDIA GeForce GTX 680 2GB GDDR5 graphics card has dual-link DVI-I and DVI-D outputs along with a DispalyPort and HDMI output headers. The GeForce GTX 680 fully supports HDMI 1.4a, 4K monitors (3840×2160) and multi-stream audio. One of the major features of the GeForce GTX 680 is an all-new display engine that is capable of driving up to four displays at once. This means you can now run 3D Vision Surround on three displays from a single GeForce GTX 680. The fourth panel has to be used as an accessory display and cannot be part of the surround setup.
The back end of the GeForce GTX 680 has a small opening to allow airflow to enter the fan.
The NVIDIA GeForce GTX 680 video card requires a 550 Watt or greater power supply with a minimum of 38 Amps on the +12V rail and two 6-pin PCI Express power connectors for proper connection. It should be noted that the NVIDIA minimum system power requirement is based on a PC configured with an Intel Core i7 3.2GHz CPU. These are pretty reasonable power requirements, so that is good news for everyone!
The NVIDIA GeForce GTX 680 graphics cards has full SLI support and comes with a pair of SLI bridges located along the top edge of the graphics card. The NVIDIA GTX 680 series supports two, three, and quad SLI configurations.
Over the past several video card series, NVIDIA has spent a great deal of time improving the cooling system and the GeForce GTX 680 is no different. Three key features allow the GeForce GTX 680 to deliver a quiet gaming experience: acoustic dampening material used in the GPU fan, an embedded triple heatpipe design, and a custom fin stack that’s been shaped for better airflow.
When it comes to noise levels, NVIDIA states that the GeForce GTX 680 runs at just 46dB. This means that the GeForce GTX 680 is 1dB lower than the GTX580 (47dB) and 7dB lower than the GeForce GTX 480 (53dB). NVIDIA also told us that the GeForce GTX680 is 5dB quieter than the AMD Radeon HD 7970 under load.
This image shows the new triple heatpipe design embedded into the base of the GPU heatsink that draw heat off the GK104 GPU and is cooled by the custom fin stack.
Let’s take a closer look at this new cooler in the GTX680 video card by taking it apart!