GTX 780 OC 6GB vs. R9 290X 4GB Overclocked at 4K

We take the ASUS STRIX GTX 780 OC 6GB video card and run two in SLI and overclock both of these at 4K resolutions to find the ultimate gameplay performance with 6GB of VRAM. We will also compare these to two overclocked ASUS Radeon R9 290X DirectCU II CrossFire video cards for the ultimate VRAM performance showdown.


We've recently been taking an in-depth look at the new ASUS STRIX GTX 780 OC 6GB DirectCU II video card in multiple testing and gaming scenarios. In our initial evaluation we were allowed to provide for you an early full-evaluation of this new video card before its official launch date. The ASUS STRIX GTX 780 OC 6GB video card brings some new technologies to NVIDIA's GeForce GTX 780 GPU which the video card is based on for an MSRP of $579. Currently street price is $599.99 at Newegg.

The first exciting technology is the STRIX technology which allows this video card to run at idle without the fans spinning. The video card can even do some light gaming and video watching without the fans turning on at all. When the temperature reaches a certain level, 65c, then the fans spin up slowly. The fans are intelligently controlled with minute changes possible that allow the RPMs to spin very slowly, and ramp up as needed. The goal is to keep noise down and allow the video cards to be as quiet as possible. In our evaluation we found that this technology is a success. It works as intended, and works well. Even with the fans running at low RPMs we had excellent temperature results on the GPU itself in heavy gaming.

The second exciting technology about the ASUS STRIX GTX 780 OC is the fact that these video cards have double the RAM of a standard GeForce GTX 780. These video cards have 6GB of VRAM installed. The goal with this is to allow high resolution gaming with high settings and AA. More VRAM is especially important at large display sizes like 4K gaming.

When we originally tested one STRIX GTX 780 OC 6GB in gaming up to 2560x1600 we found that this resolution was not stressing the video cards VRAM at all. We were held back simply by performance, and not VRAM at up to 1600p on a single video card. We then expanded our testing in a follow-up evaluation to two ASUS STRIX GTX 780 OC 6GB video cards in SLI. In our ASUS STRIX GTX 780 OC 6GB SLI evaluation we pushed these video cards much harder by running in a 3x1 NV Surround setup and on a 4K display. These configurations pushed the cards farther, further showing us the advantages of 6GB of VRAM at high resolution gaming.

We also did another follow-up evaluation overclocking one single ASUS STRIX GTX 780 OC 6GB video card up to 1600p. Our results were positive from overclocking showing improved and gameplay performance noticeable changes from being overclocked.

Pushing ASUS STRIX GTX 780 OC 6GB SLI Further

In this, our final look at the ASUS STRIX GTX 780 OC 6GB we are going to focus on both overclocking and SLI together now. In our ASUS STRIX GTX 780 OC 6GB SLI evaluation we talked about the need for more performance to truly utilize the 6GB of VRAM on both cards in a more pronounced way. We indicated that all that was holding these cards back is performance.

We had feedback in our discussion forum questioning what these cards would like if we had overclocked these in SLI. By overclocking these we'd be gaining more performance potentially giving these an advantage over the competition which only has 4GB of VRAM. Overclocking these cards would allow us to utilize more of that VRAM by running at higher settings at the high resolutions tested.

This evaluation today is going to push the ASUS STRIX GTX 780 OC 6GB video cards to the max by overclocking these in SLI and playing games at 4K (2160x3840) specifically. We are going to answer several questions pertaining to overclocking 6GB video cards versus the competition at 4K in SLI.

First we want to find out if overclocking is even advantageous to performance in SLI. We want to see if we can improve the gameplay experience, and if performance improvements are noticeable and positive.

Then we want to find out the value of the ASUS STRIX GTX 780 OC 6GB video cards compared to the competition when overclocking performance in SLI (not just base performance) is taken into account along with the price.

Third we want to utilize the improved performance from overclocking in SLI to see if the 6GB of VRAM is advantageous to gameplay performance also compared to the competition. We want to see if this VRAM upgrade is allowing us to play at higher settings overclocked.

Finally we want to be able to tell you what is best for gaming when it comes to forward looking, next generation gaming at 4K display resolution. Should you save money and go with the AMD Radeon R9 290X 4GB in CrossFire, or is better to go 6GB with the ASUS STRIX GTX 780 OC 6GB SLI?

How We Are Going to Pull This Off

In order to accomplish all the results above we are going to be overclocking both the ASUS STRIX GTX 780 OC 6GB SLI cards and the AMD Radeon R9 290X GPU based cards. In order to provide the best competition, and similar pricing, we are going to forgo the usual XFX Radeon R9 290X Double Dissipation video cards we've been using and use two straight up ASUS Radeon R9 290X DirectCU II video cards for comparison.

We are using these ASUS cards for two reasons, firstly these will give us better overclocking potential than the XFX cards and second is the price. The ASUS Radeon R9 290X DIrectCU II costs $559 right now and the ASUS STRIX GTX 780 OC 6GB video cards we are using cost $579. Therefore pricing is very similar with the ASUS R9 290X DC2 cards having a slight price advantage.

We are also going to be doing all of our testing solely on a 4K display today at 2160x3840. There are several reasons for this. First, at 4K (2160x3840) you are pushing more pixels than our standard 3x1 NV Surround setup at 5760x1200. The resolution of 3840x2160 consists of 8,294,400 pixels while 5760x1200 consists of 6,912,000 pixels. By pushing more pixels we are testing better the usage of the 6GB of VRAM compared to the 4GB of VRAM on the R9 290X. The greater pixels also demand more performance. Overclocking yields better results to gameplay performance when the video cards need to work harder to accelerate the game. The higher resolution, pixels, will show overclocking advantages better.

4K needs a lot of performance from video cards to make gaming viable at high settings. Even R9 290X and GTX 780 SLI cannot max out some games at 4K, so we need all the improved performance we can get to improve the gameplay experience at 4K. Finally we want to show you what the future of gaming (or now since there are now some affordable 4K gaming displays) will be.


Article Image Article Image

Above you can see the ASUS STRIX GTX 780 OC 6GB video cards in SLI in our test system. We had no issues configuring these and running at 4K resolution. NVIDIA's software automatically stitches the displays together to run at 3840x2160 with no input needed from us once the driver is installed. There are lights on the back of the video cards on the power connectors to let you know power is connected correctly or not.

Article Image Article Image

Above are the comparison ASUS Radeon R9 290X DirectCU II CrossFire video cards we are also going to be overclocking for comparison.