NVIDIA Kepler GeForce GTX 680 SLI Video Card Review
We've got two GeForce GTX 680 video cards to test SLI performance against Radeon HD 7970 CrossFireX. Will these less expensive GTX 680 video cards offer a better gameplay experience or choke at high resolutions due to a smaller VRAM footprint? We will prove to you which solution offers better efficiency and performance.
GeForce GTX 680 SLI
On March 22nd, 2012 NVIDIA debuted its next generation GeForce GTX 680 video card, based on the Kepler GPU. While there will be more in the Kepler family later on, currently the GeForce GTX 680 represents NVIDIA's flagship video card at $499. This provides a competitive price point to AMD's Radeon HD 7970 flagship video card at $549. While there is a $50 price difference, we found that GeForce GTX 680 more than keeps up with Radeon HD 7970. In fact, at 1080p the GTX 680 outperforms Radeon HD 7970 and provides a better gameplay experience in our single-video card testing.
We looked at performance at 2560x1600 and 5760x1200 with a single-video card previously. What we didn't have a chance to look at, until now, was how two GeForce GTX 680 video card perform in SLI, and the kind of gameplay experience we are provided. This evaluation focuses on GeForce GTX 680 SLI performance compared to Radeon HD 7970 CrossFireX performance and we threw in a GTX 580 SLI for comparisons’ sake.
There is nothing "new" when it comes to the GTX 680's SLI support. In the past generation you could setup NV Surround with two video cards, and you can do that again. Setup is extremely easy, with only one bridge connector required. With two GTX 680 video cards you'll need 4x 6-pin connectors in total, whereas with Radeon HD 7970 CrossFireX you'll need 2x 8-pin and 2x 6-pin connectors.
To setup our triple-display configuration for testing in NV Surround we utilized all the DVI connectors. We plugged two displays into the primary card, and the third display into the secondary card, all on DVI. NV Surround is a snap to setup in the control panel, and it only takes a few seconds, you don't even need to reboot. Both AMD's and NVIDIA's setup is simple, quick, and both worked without issue.
To make our SLI solution work we are using one NVIDIA GeForce GTX 680 reference video card and one GALAXY GeForce GTX 680 video card, which is a reference design at this time. (Galaxy, will be selling its own card very soon.) Both cards we have run at the same 1006MHz baseclock. With the nature of GPU Boost, both video cards can run at independent clock speeds. This means that GPU Boost can be boosting each GPU separately as it needs to for the best performance, the clock speeds don't have to match up. This provides the best performance at all times based on GPU utilization, power, temp and other things. We will be testing on three Dell 2408WFP displays at 5760x1200.