ASUS STRIX GTX 780 6GB OC Edition Graphics Card Review

Even though NVIDIA and AMD haven’t released new GPU platforms as of late, that’s not stopping ASUS from finding innovative ways to enhance the user experience on existing GPUs. To that end, ASUS recently announced a new line of cards that carry the STRIX branding. Initially, there will be AMD R9 280 and NVIDIA GTX 780 versions released. Today, we’ll be looking the the NVIDIA offering in the form of a GTX 780 OC Edition. The ASUS STRIX GTX 780 OC Edition comes complete with a factory overclock, an astounding 6 GB of memory, and a revised DirectCU II cooling methodology. Ok, I’m intrigued. Let’s run this card through the paces and see what ASUS has in store for us this time around!

Specifications and Features

Looking at the specifications below, the first thing that pops out is the 6 GB of onboard GDDR5 memory. That’s twice the amount found on standard GTX 780 cards and should make the 4K and multi-monitor gamers a happy lot. The memory sits on a 384-bit interface and is rated at 1502 MHz (6008 MHz quad-pumped). The factory overclock is a little on the mild side with only a 26 MHz base clock bump from the reference design. The boost clock sees a 41 MHz boost from the reference design, but we all know the actual boost clock speed will be substantially higher when the GPU is under load.

A quick glance at GPU-Z confirms the specifications above and gives us a few more tidbits of information.

As is typical with most ASUS products we review, they were kind enough to provide a series of slides depicting the features of the STRIX GTX 780 OC Edition. On a high level, the features can be broken down into gaming performance, the new 0dB fan technology incorporated into the DirectCU II cooler, power delivery, and the GPU Tweak software.

ASUS performed their own in-house testing to illustrate the performance gain the STRIX GTX 780 OC Edition provides over the reference design cards. They claim anywhere from 3.7% up to 15% faster performance, depending on the game/benchmark.

Probably the most intriguing new feature brought forward with the STRIX GTX 780 OC Edition is the 0dB fan technology added to the DirectCU II cooling scheme. The fan blades will not begin spinning until the GPU temperature reaches 65° C, which is where the marketing slogan of “Absolute Silence” is derived. Under light usage scenarios such as internet browsing and productivity tasks, it’s likely the fans will never start spinning at all. I can see this being a nice feature when watching movies or listening to music, where a quiet system is at a premium. Even when the fans are spinning to keep the card under the 65° C threshold, ASUS claims the DirectCU II cooler will keep the GPU temperatures 38% under that of the reference design cooler. ASUS also claims 3X quieter operation, which is definitely believable if you’ve ever heard one of those reference design “turbine engine” sounding fans.

The actual design of the DirectCU II cooler uses heatpipes that make direct contact with the GPU and weave their way through a massive 4112 cm² dissipation area. ASUS puts their faith in this design to passively cool the GPU under light usage. An additional layer of heat dissipation is provided by the included backplate, which also serves to provide PCB protection and stiffening. One thing you’ll definitely need is good case cooling in order for this revamped DirectCU II cooling method to work at its best.

Here is a video showing the DIrectCU II cooler with odB fan technology at work.

The 10-phase power design encompasses the use of ASUS’ DIGI+ VRM and Super Alloy Power components. The all digital DIGI+ VRM is said to be programmed to adjust voltage according to different overclocking scenarios, which can lead to lower power noise when compared to analog VRM designs. The DIGI+ VRM is also said to provide 15% better power efficiency due to its ability to intelligently transfer current among the 10 power phases. ASUS also implements SAP caps directly under the GPU, which improves access to their capacitance and can help overclocking. Also aiding in overclocking potential ares the hardened MOSFETs that are said to offer a 30% higher voltage threshold than the reference design. The SAP chokes have a “concrete like” alloy filling, which helps eliminate buzzing sounds that may be present with standard chokes. ASUS also uses all 5K solid capacitors throughout the PCB that have a 2.5X longer lifespan than traditional capacitors.

Even the power connectors themselves have a couple unique features worth mentioning. The first being that the connectors are positioned with the lock tabs facing away from the heatsink. It should make releasing the power cable’s latch a lot easier. There are two LEDs located in this area to indicate proper power cable installation. When installed correctly, the LED will be white. If you forget to install a power cable or install it incorrectly, the LED will be red. I like that ASUS changed the “good connection” LED color to white from the green I’ve seen them use in the past. The white LEDs tend to blend in much nicer with the interior looks of a chassis.

On the software side, GPU Tweak can be used for real-time overclocking and monitoring capabilities. GPU Tweak Streaming is also available if you wish to broadcast your game play live over the internet.

Packaging/Accessories/First Look

The retail box has a familiar ASUS theme we’ve seen plenty of in the past. The front gives you basic information on the high-level features and an exploded view of the DirectCU II Cooler. Around back is where you’ll find more detailed descriptions of what the card has to offer. The box sides are used for additional branding and a multilingual list of recommended system requirements.

This slideshow requires JavaScript.

Inside the outer sleeve is another black box that houses the STRIX GTX 780 OC Edition and all the accessories. You’ll find the product well-secured in a foam bed and properly wrapped in an anti-static bag. The accessories are housed in a smaller box of their own and include the following items.

• Support DVD
• User/Install Manual
• DVI to VGA Adapter
• Flexible SLI Bridge
• Power Adapter Cable
• STRIX Case Badge

This slideshow requires JavaScript.

Photo Op

The mostly black color scheme is accented with a hint of red from the stickers attached to the center hub of each fan. As is the norm with ASUS, aesthetics play a large part in their design efforts. It’s a nice looking card no matter what angle you gaze at it from and should be a great match for any system build using a similar color scheme. Enjoy the pictures!

The STRIX GTX 780 OC Edition Up Close

Taking apart a graphics card requires skillful use of overly expensive and precision screwdrivers. In my case, that means nothing more than using $2 screwdrivers I purchased at a flea market. In all seriousness, taking this card apart was a snap to accomplish and only entailed removing four spring loaded screws from the backside. Once removed, the DirectCU II cooler was found to be making perfect contact with the GPU with just the right amount of TIM applied. With the TIM cleaned off, we see the where the heatpipes make direct contact with the GPU. The contact surface, while not polished to a mirror finish, is smooth to the touch.

The aluminum shroud can also be removed to expose the coolers fin array. The two fans are attached to the fin array and are FirstD branded, which is what we normally see ASUS use here. I measured the fans and came up with right at 92 mm in circumference. The five heatpipes are comprised of two that are 6 mm, two that are 8 mm, and the largest is a single 10 mm affair.

Taking off the backplate requires removing several additional screws, which are accessed from the topside of the card. Once off, we can see the SAP caps located directly behind the GPU core. The backplate itself doesn’t make direct contact with components on the back of the card and actually uses built in standoffs to keep it from doing so. I think ASUS could improve a bit on this design by using thermal pads and allowing the backplate to make contact with at least the MOSFET area.

Having a closer look at the power delivery area, it’s no surprise ASUS has beefed this up when compared to the reference design. The 10-phase power design consists of eight phases for the GPU and two more for the memory, whereas the reference design uses six for the GPU and two for memory. There is a small heatsink attached to the MOSFET area to provide additional cooling… good move there! The heatsink uses a thermal pad and was found to be well-attached and making excellent contact. The last picture below is a close-up view of the 5K solid capacitors found scattered about the PCB.

In order to bring power to this stout 10-phase power design, you’ll need an 8-pin and 6-pin power cable from your PSU. Once the power is being delivered, the voltage regulation duties will be handled by the DIGI+ VRM controller.

The GPU core is surrounded by 12 of the ever popular SK Hynix memory chips. In the case of this particular card, part number H5GC4H24MFR-T2C chips are used. These memory chips are 512 MB each and run at a rated speed of 6 GB/s using up to 1.5 V.

That last two pictures below are of the Kepler GK110-301-B1 GPU core. Yes, the same GPU core found in the GTX 780 Ti models, albeit a trimmed version.

ASUS GPU Tweak Software

Over the years, GPU Tweak has evolved into a feature rich and robust graphics card tuning utility. The utility offers overclocking, monitoring, voltage adjustments (where applicable), and fan speed control. Available as a separate install is GPU Tweak Streaming, which we’ve already touched on in the features section above.

From the Tuning section, you have all your overclocking, voltage, and fans speed control options.

This slideshow requires JavaScript.

Under the Live Update section, you can choose to have GPU Tweak automatically check for updates and apply them if any are found. The Settings section has four sub tabs dealing with how the utility looks and works at system start-up. You can also setup any hotkeys you might want from here as well.

This slideshow requires JavaScript.

When the CPU Info section is selected, a slide out window appears to the right showing the integrated copy of GPU-Z. From any screen, the three icons at the lower left corner can be accessed. You can launch a predefined benchmark by clicking on the arrow button, toggle between standard and advanced mode by clicking on the center button, or launch the pop out monitoring window by clicking the bottommost button.

This slideshow requires JavaScript.

Overclocking

Heading out in search of a 24/7 stable overclock, I landed at a GPU speed of 1089 MHz base clock and 1140 MHz boost clock. This resulted in an actual boost clock of 1254 MHz when under load. The memory landed at 1824 MHz or 7296 MHz quad pumped. That’s a 19% GPU overclock and 18% on the memory side. When I say 24/7 stable, I mean being able to complete our entire suite of synthetic and game benchmarks with no artifacts.

Benchmarks

Test System

We have a competitive group of comparison cards on the docket for today’s benchmarks results, so let’s get to it! We’ll stick to the Overclockers.com GPU test procedure that we’ve been using since the Haswell platform was released. If you’re not familiar with our testing method, click on the link provided for more information. For quick reference, below is the down and dirty version of what we do.

System Requirements

• i7 4770K @ 4 GHz
• Dual Channel DDR3-1866 9-9-9-24
• GPU @ stock and overclocked
• Monitor capable of 1920×1080

Synthetic Tests

• 3DMark Vantage – DirectX 10 benchmark running at 1280X1024 – Performance preset.
• 3DMark 11 – DirectX 11 benchmark running at 1280X720 – Performance preset.
• 3DMark Fire Strike – DirectX 11 benchmark running 1920X1080 – Standard test (not extreme).
• Unigine Heaven (HWBot version) – DX11 Benchmark – Extreme setting.

Game Tests

• Batman: Arkham Origins – 1920X1080, 8x MSAA, PhysX off, V-Sync off, The rest set to on or DX11 enhanced.
• Battlefield 4 – 1920X1080, Ultra Preset, V-Sync off.
• Bioshock Infinite – 1920X1080, Ultra DX11 preset, DOF on.
• Crysis 3 – 1920X1080, Very high settings, 16x AF, 8x MSAA, V-Sync off.
• Final Fantasy XIV: A Realm Reborn – 1920X1080, Maximum preset.
• Grid 2 – 1920X1080, 8x MSAA, Intel specific options off, Everything else set to highest available option.
• Metro Last Light – 1920X1080, DX11 preset, SSAA on, Tessellation very high, PhysX off.

Synthetic Tests

Synthetic benchmarks show the STRIX GTX 780 OC Edition falling right where it should in the pecking order. The EVGA GTX 780 SC has a higher factory overclock, so its slightly better scores in three of the four tests is expected. However, the STRIX GTX 780 did manage to top the EVGA offering in HWBot Heaven while trading blows with the R9 290 samples in the other benchmarks. Once the STRIX GTX 780 was overclocked, it held tight to the EVGA GTX 780 Ti and the scores scaled very well.

Game Benchmarks

As you look through the game benchmarks, you’ll see a similar pattern as above. The STRIX GTX 780 actually topped the EVGA GTX 780 SC a time or two and continued to swap victories with the R9 290 comparison samples. Once overclocked, the STRIX GTX 780 managed to top the R9 290X most of the time as well.

Surround/Eyefinity Benchmarks

I ran several of our most popular game benchmarks to test Surround performance of the STRIX GTX 780 OC Edition. The 6 GB of onboard memory will be much appreciated by those that game with multiple monitors or even with 4K monitors. Today’s latest gaming titles are becoming more and more demanding and require larger amounts of onboard memory. This card should provide plenty of memory for today’s most demanding games and future titles as well.

The results below were obtained with the benchmarks set to the same settings as above, but with the resolution set to 5760X1080. Three of the five benchmarks eclipsed the 30 FPS mark we consider the lowest “playable” frames per second. As is usual with every video card we’ve tested to date, Crysis 3 and Metro: Last light will need a setting or two relaxed in order to achieve that magical 30 FPS at 5760X1080 resolution. We didn’t have Surround/Eyefinity results for all the cards used in the above graphs, so I substituted a couple with cards we do have results for.

Power Consumption and Temperatures

Power consumption tests are done using a Kill-a-Watt meter with the highest observed reading shown in the graph below. In the past, I’ve used the 3DMark 11 combined test to get one of the results, but I have since found that 3DMark Fire Strike’s combined test actually results in a higher wattage use. So. I’ve switched over to that for one of the power consumption tests. The other test is still performed using HWBot Heaven.

As you can see by the results below, total system power draw stayed well below 400 watts when the card was left at stock speed and under full load. This is somewhat due in part to the DirectCU II fan only getting up to about 40% once under heavy load. Once overclocked, the total system draw topped the 400 watt mark as expected. Idle power draw is quite impressive with just over 100 watts being recorded. Obviously, the low idle power draw is aided by the DirectCU II fans never starting up while under this low load situation.

The 0dB fan technology works just as advertised, and the fans took quite a while to fire up once the card was put under load. The DirectCU II cooler does an admirable job as a passive cooler, especially under average to low load scenarios. The highest temperature recorded was 75° C with the fan left on auto control and the card overclocked. The testing was done on an open air bench station, so once buttoned up in a case the temps are likely to be a little higher than that. As previously mentioned, a good case air flow scheme will be necessary to take full advantage of the 0dB fan technology and its benefits.

Pushing the Limits

One final effort to see how far I could push the card and complete a run of 3DMark Fire Strike landed us at clock speeds of 1103 Mhz base, 1155 MHz boost, and 1267 actual boost. Memory overclocking took us up to 1838 MHz (7352 MHz quad pumped). All told, that produced a score 145 points higher than our previous overclocked score. I think the card probably has more in it, but I was right at the maximum power target limit of 110%. Anthing further would undoubtedly result in GPU clock speed throttling.

Conclusion

The ASUS STRIX GTX 780 OC Edition performed exactly as expected given its out-of-box GPU clock speed. It overclocked very well too, which resulted in a good amount of increased performance. The 0dB fan technology ASUS programmed into the vBIOS is a unique feature that will be a definite plus if you’re into quiet gaming, or even while enjoying multimedia sessions. While it may be true the same fan effect can be accomplished using GPU Tweak’s custom fan control options, it does keep you from having to set that up and having the utility load at system start-up. Alternatively, if you prefer to have fans running all the time, that too can be done through GPU Tweak.

Having 6 GB of memory on a GTX 780 based card is going to be something multi-monitor and 4K gamers will look seriously at. It’s good to see NVIDIA has allowed partners to offer a 6 GB version of this card, because I doubt you’ll ever see it on a GTX 780 Ti series card. If NVIDIA allowed 6 GB of memory on the GTX 780 Ti, it would pretty much make the GTX Titan irrelevant with it’s hefty price tag. Time will tell though, and we’ll see what happens down the road.

ASUS tells us the card should be available in retail channels by June 23rd and will carry a retail price of $579. At that price it’s actually a little less expensive then the only other 6 GB GTX 780 currently available at Newegg right now, which is the MSI N780. So, I think the STRIX GTX 780 OC Edition is right about where it should be price wise.

In the end, we have yet another solid offering from ASUS that brings enthusiasts another choice when considering a GTX 780 based graphics card. Great performance, good overclocking, solid aesthetics, unique cooling, and a fair price… easy call this time around!

Click the stamp for an explanation of what this means.

–Dino DeCesari (Lvcoyote)