ASUS GTX 660 DirectCU II TOP Review

ccokeman - 2012-08-10 17:50:51 in Video Cards
Category: Video Cards
Reviewed by: ccokeman   
Reviewed on: September 13, 2012
Price: $249

Introduction:

Just a few short weeks ago NVIDIA delivered the GTX 660Ti to the world, proving that the scalable Kepler architecture could indeed be used to power the mid range and with its GK106 core in the largest segment of the video card pie. The $299 price point and lower is the largest segment of that pie and has been a price point the Kepler architecture has not reached successfully until now. The GTX 660Ti got close at $299 but realistically was not going to reach the $250 range. Now just three weeks after the GTX 660Ti dropped the GTX 660 is here to fill that void and deliver gaming performance to the masses at a more appealing sub-$250 price point with reference models starting at $229. At this low price point you still get all of the features and capabilities of of NVIDIA's Kepler architecture including 3DVision, PhysX, GPU Boost, Adaptive VSync, and TXAA - a new anti-aliasing algorithm designed to reduce temporal aliasing. Having looked at the entire Kepler product stack so far from the top of the line dual and single GPU cards with the GTX 690 and GTX 680 as well as the more affordable GTX 670 its clear to see the strategy to bring a card to each segment.

The GTX 660 is equipped with NVIDIA's all new GK106 core using the same GPC/SMX setup that has proven so effective in the upper end GK104. Packed with 960 CUDA cores clocked at 980MHz from the factory and able to run 2GB of GDDR5 memory clocked at 1502MHz (6008MHz effective) through a 192-bit bus, the GTX 660 is targeted squarely at a the 1920x1080 resolution gaming crowd. When compared to previous generation non-DX11 and even NVIDIA's own Fermi-class DX11 cards, the GTX 660 is going to offer an incredible jump in performance and visual capabilities when moving from a DX10 card. As most game developers make the move to DX11, hardware will need to keep up allowing the end user the ability enjoy all the effects the games have to offer. With many free-to-play titles already making the move to DX11, the market for the sub-$250 price point is ready and waiting to take advantage of the latest DX11 capable hardware, including the GTX 660. With the strong overclocking capabilities of the Kepler architecture, many of the board partners will be releasing factory overclocked cards with improved voltage controls, better PCBs, and much improved cooling.

ASUS' GTX 660 DirectCU II TOP is, pardon the pun, ASUS' top end card in its GTX 660 product stack using its own Digi+VRM design, Super Alloy Power components, and impressive Direct CU II cooling to deliver a card that will make it reliably to the next upgrade cycle and beyond. Pricing for the TOP version will be right under the $250 price point at $249. Knowing where the GTX 660 is targeting the performance, testing should prove interesting.

Closer Look:

The GTX 660 uses the full scale implementation of NVIDIA's 28nm GK106 Kepler SMX architecture introduced with the GTX 680. As such this design is the pinnacle product for the GK106 core. This implementation on the GTX 660 features three Graphics Processing Clusters (GPC) with shared access to the L2 cache, five SMX units, each with 192 CUDA cores (960 total), 80 texture units, and 24 ROPs. Base clock speeds for the reference version come in at 980MHz with a boost clock of 1033MHz on the GK106 core. Clock speeds on ASUS DirectCUII TOP are significantly higher with a base clock of 1072MHz and a boost clock 104+MHz higher than the reference version at 1137MHz. The memory subsystem of the GTX 660 supports mixed density modules allowing 2GB of GDDR5 memory to be used instead of 1.5GB through the 3 x 64-bit (192-bit) memory controller. Memory clock speed will remain unchanged from that of the GTX 660Ti at 6008MHz effective. GK106 will support GPU Boost technology from NVIDIA, which allows the GPU core clock speeds to run over and above the factory defined base clock speed so long as the TDP of 140W is not exceeded.

 

Externally the ASUS packaging mirrors what we saw with the GTX 660Ti with the main focus targeted towards the feature set of the GTX 660. First and foremost is that this version of the GTX 660 from ASUS is the DirectCUII TOP factory overclocked variant equipped with a heat pipe direct contact cooling solution successfully employed from the top to the bottom of the ASUS Kepler-based product stack. The GPU model is clearly stated along with the large 2GB frame buffer, ASUS Digi+VRM with Super Alloy Power (SAP)components, and that ASUS own GPU Tweak overclocking and monitoring utility can be used with the GTX 660 DirectCUII TOP. The back side of the package expands on what the feature set brings to the table and how the DCUII cooling solution is 20% cooler than reference designs and that ASUS Digi+VRM and SAP feature set runs with 30% less power system generated noise, runs 15% more efficiently, and has the ability to extend logevity over the reference design by two and a half times.

 

 

The inner package is black in color and has the ASUS logo embossed in gold. Internally ASUS has moved away from a full foam block cut out to fit the GPU and uses a more cost and environmentally friendly cardboard enclosure with only a small amount of plastic strecth wrap to hold the GPU in place. It is surprisingly effective at holding the GTX 660 DirectCU II in place during shipment. The bundle of accessories is slim to say the least but really at this price point you get all that you will need. Included are the Quick setup guide, driver disk, and a DVI to VGA adapter. Additional power connections are not needed since the GTX 660 DirectCUII TOP uses just a single 6-pin PCIe power connection supplied on just about every power supply over the past few years. Grabbing the latest drivers from NVIDIA's website will ensure you get the latest compatibility and game fixes.

 

 

The GTX 660Ti proved to be a card that could handle 1920x1080 gaming with high settings and even deliver some 5760x1080 surround gaming when the in-game settings were reduced to the medium/high level. The GTX 660 will have no illusions of surround gaming on its own and is targeted squarely at the 1920x1080 resolution where the majority of gamers are now playing. Let's see what ASUS has for us with this highly binned GTX 660 DirectCU II TOP.

Closer Look:

ASUS' GTX 660 DirectCU II TOP is the top card in its GTX 660 product stack. As a non-reference design the GTX 660 DirectCU II uses a custom PCB loaded with ASUS own specific technologies including the use of its Digi+VRM all digital power circuit featuring Super Alloy Power components including custom Chokes, MOSFETs, and capacitors. The GTX 660 comes in several flavors from ASUS to meet different performance and price targets. The TOP version that I am looking at has been through a rigorous testing and validation process that allows the card to run with a base clock of 1072MHz, boost clock speed on the core of 1137MHz or 104MHz above the reference GPU boost clock speed of 1033MHz. Each part of the card endures this testing and validation process to deliver long term reliability and stability. A first look of the card shows that the DirectCU II cooling solution is the most visible feature of the card. It employs a pair of 70mm "Dust Proof fans" to provide the up to 600% improvement in airflow over the reference design needed to keep the card cool and extend the life of the fans by up to 25%. That large increase in airflow allows the GTX 660 DirectCU II to run 78% cooler and 9dB quieter than the reference design. This card measures just 10.2 inches in length and is a two slot card with the DirectCU II cooling solution. Designed to be used in a 16x PCIe 3.0 expansion slot, the card is backwards compatible with PCIe 2.0 motherboards.

The back of the custom black PCB is mostly vacant with the exception of four of the mixed density GDDR5 modules seen surrounding the GPU socket. In the center of the socket area is part of the Digi+/SAP power package called the SAP cap. These capacitors store additional current right behind the GPU to provide that instantaneous boost of current needed to keep up with the current draw of a highly overclocked core improving stability under load. Looking at the top and bottom of the card the three 8mm "Direct Contact" nickel plated copper heat pipes that loop around and into the aluminum fin array are visible. The heat load is exhausted both into and out of the chassis but will not provide enough thermal dump into the chassis to overcome the vast majority of chassis airflow solutions. Aesthetically the GTX 660 mirrors the ROG inspired look of the rest of the DIrectCU II lineup. Putting the GTX 660 DirectCU II into any of ASUS' own ROG motherboards would be a perfect visual fit.

 

 

 

 

 

 

 

 

 

Connectivity on the GTX 660 DCU II consists of a single Dual Link DVI-I port, one Dual Link DVI-D, a single HDMI 1.4a port, and a single full-size DisplayPort 1.2 port. The maximum supported resolution is 2560x1600. Targeted for gaming with a resolution of 1920x1080, jumping to a triple screen surround setup will need a second card in SLI. However the GTX 660 can make use of another part of the NVIDIA ecosystem by using 3D Vision to deliver an additional dimension to your gaming experience. The back end of the GTX 660 DCU II has the shroud stopping at the end of the PCB with the PWM fan header on the bottom edge of the PCB.

 

 

Across the top of the PCB is a support brace used to keep the PCB from bending and cracking the trace routes in the PCB. A single SLI bridge connection is used to support just one other GTX 660 in an SLI configuration at this price/performance point. With a 140 watt TDP, a single 6-pin PCIe power connection is used. Starting the system up after a new build is a rush for most people. When everything powers up all is right in the world until you do not get a video feed. To combat this ASUS has incorporated its Protective Design feature set into this card with part of the feature set being the VGA LED. This feature gives the user a visual cue indicating whether they have power to the PCIe connection points on the card. Red means no power and to connect the power plugs, and green means all is well with the requisite 6-pin PCIe power connections in place. That bright red eye caught me in the rush to test this card.

 

 

ASUS' DirectCU II cooling solution is the most outwardly visible feature on this card. It utilizes three 8mm nickel plated copper heat pipes that flatten out as they travel through the contact surface to distribute the thermal load to the aluminum fin array. This aluminum fin array has five separate dissipation points and an optimized pitch design to most efficiently channel the load from the GPU to the airstream generated by the two 70mm dust proof fans. These fans use a dual seal to keep dust out of the hubs increasing the life span of the fans up to 10,000 hours over cards that do not use this fan technology. The GTX 660Ti DCU II TOP used a small extruded aluminum heat sink over the Digi+ VRM/SAP six phase power circuit but this card does not have one to help manage the reduced thermal load on the VRM circuit. The contact surface, much like most heat pipe direct contact designs, is smooth to the touch but not as smooth as a one piece contact plate. Even so the design is proven to be quite effective at transferring the thermal load from the GPU core to the aluminum fin array.

 

 

As another part of the ASUS Protective Design suite, the 70mm x 10mm fans use a dust proof design to extend the useful life span of the cooling fans by up to 25% over standard designs. These fans use two seals to reduce dust intrusion into the fan hub that can slow down the fans rotation over time. Using a non-sealed design would ultimately lead to compromising the cooling efficiency of the DirectCU II design. The eleven blade fans from First D deliver substantial airflow and higher static pressure through the shroud to improve cooling by up to 78% over a reference solution. Fan noise from video cards has been one of the necessary evils with air cooling over the years with reference blower designs being the worst offenders. ASUS' DirectCU II design as it is implemented on the GTX 660 DirectCU II TOP is dead silent from outside the chassis in normal operation running at 9dB quieter than the reference design. Spinning the fans up to maximum results in only a whir from inside the chassis to go along with the great cooling performance.

 

 

Stripping away the heat sink we can get a closer look at the PCB and take a look at the component layout. The VRM circuit on this card has been put on the back end of the PCB unlike the design used on the GTX 660Ti DirectCU II TOP. On the GTX 660 DirectCU II TOP, ASUS has used a six phase all digital power circuit using its Digi+VRM/Super Alloy Power package. ASUS' Super Alloy Power technology is meant to increase efficiency, extend component life, run cooler, and reduce electronic noise. Developing components that meet these needs was paramount to delivering a card that performs well and lasts for a long time without failure. The SAP chokes use special alloys and a concrete core to reduce the buzzing so commonly heard with less robust designs. The SAP Capacitors allow a 30% increase in the maximum voltage threshold all while increasing the lifespan by two and a half times over the reference card. The Super Alloy MOS is smaller, runs cooler, and handles up to 30% more current than traditional designs and is detailed in the slide below. At the back end of the PCB is the Digi+VRM digital controller used the control this feature set while delivering monitoring and software control of card via ASUS GPU Tweak utility.

 

 

 

NVIDIA is launching a new core with the launch of the GTX 660 rather than reuse GK 104. With this launch we get the full implementation of the 28nm, 2.54 Billion transistor GK106 core that is equipped with a total of three Graphics Processing Clusters, five SMX each equipped with 192 CUDA cores for a total of 960. Texture units come in at 80 with 24ROPs. The 2GB of GDDR5 memory is running through a 3 x 64-bit memory controller that supports mixed density memory. Clock speeds for ASUS GTX 660 DirectCU II TOP are significantly higher than the reference clocks at 1072MHz for the "base" clock and 1137MHz for the "GPU Boost" clock. Increases of 92MHz on the base and 104MHz higher on the boost clock than reference designs. That's not to say the clocks will not run higher when the power envelope is not exceeded. Instead of the capable Hynix memory modules seen on just about every enthusiast level card over the past year, ASUS has used Samsung GDDR5 part number K4G20325FD-FC03 that are specified to run at 1500MHz. Clock speeds on the installed GDDR5 memory are 1502MHz (6008MHz Effective) or just above the specified range of the memory.

 

 

On strictly a hardware level the GTX 660 DirectCU II TOP is going to run slower than the GTX 660Ti. Targeted at those 9800 GT users still not enjoying DirectX 11 or even first generation Fermi cards like the GTX 460s and last year's GTX 560Ti, the GTX 660 including ASUS GTX 660 DirectCU II TOP look to offer tremendous upside with just about the entire NVIDIA ecosystem including PhysX, 3DVision, and more.

Specifications:

Model:
GTX660-DC2T-2GD5
Graphics Engine:
NVIDIA GeForce GTX 660
Bus Standard:
PCI Express 3.0
Video Memory:
2 GB GDDR5
GPU Boost Clock:
1137 MHz
GPU Base Clock:
1072 MHz
CUDA Cores:
960
Memory Clock:
6008 MHz Effective
Memory Interface:
192-bit
DVI Max. Resolution:
2560x1600
DVI Output:
Dual-link DVI-I + Dual-link DVI-D
HDMI Output:
1x Native
DisplayPort:
1x Native (Full size)
HDCP Compliant:
Yes
Adapter Bundled:
1x DVI to D-sub adapter
Software Bundled:
ASUS Utilities and Driver, GPU Tweak
Dimension:
10.2" x 5.2" x 1.5"

 

 

Features:

 

 

 

All Information Courtesy of ASUS and NVIDIA

 

 

Testing:

Testing of the ASUS GTX 660 DIrectCU II TOP  will consist of running it and comparison cards through the OverclockersClub.com suite of games and synthetic benchmarks. This will test the performance against many popular competitors. Comparisons will be made to cards of a range of capabilities to show where each card falls on the performance ladder. The games used are some of today's newest and most popular titles, which should be able to provide an idea of how the cards perform relative to each other.

The system specifications will remain the same throughout the testing. No adjustment will be made to the respective control panels during the testing, with the exception of the 3DMark 11 testing, where PhysX will be disabled in the NVIDIA Control Panel, if applicable. I will first test the cards at stock speeds, and then overclocked to see the effects of an increase in clock speed. The cards will be placed in order from highest to lowest performance in each graph to show where they fall by comparison. The latest press release driver will be used in testing of the GTX 660, with the 660Ti tested with the release driver; AMD will be using Catalyst 12.6 drivers.

 

Comparison Video Cards:

 

Overclocking:

Overclocking this ASUS GTX 660 DIrectCU II was accomplished using ASUS' latest version of its GPU Tweak (Version 2.2.0.1) utility. When Kepler-based cards first launched there were concerns that overclocking would be limited due to how the onboard monitoring would down clock the card to keep within the power and thermal limits of the GPU. In fact there was just another wrinkle added to the process. Manage the thermals and only adjust voltage enough to reach the next clock speed plateau and all is good. If the power draw gets too high the symptoms will be that gaming performance or benchmarks will be drastically reduced from the expectations.

Starting out on this card I increased the power limit to its maximum level of 110%, bumped the fan speed to 100% and started bumping up the boost clock and running the card through some preliminary stress testing to find the limit on the core. I kept boosting and testing and bumping the core voltage in small steps until I reached a level where voltage would not fix the stability issues. I then followed the same process for the memory without the voltage increases until the game tests would fail. To that end it took 1100mv to reach the 1206MHz boost clock on the core and 1634MHz (6538MHz Effective) clock on the memory. The boost speed may not seem all that impressive but consider that it would go between the 1220 to 1233MHz range in just about every game with the card under the 110% power envelope. All told that is a +69MHz boost over the already impressive 1137MHz factory boost clock and 135MHz higher than the factory memory clock. Free performance at its finest. By boosting the fan speed to 100% the card never saw the high side of 59 °C in my testing. At 64 °C the stock cooling performance is good but it gets better as expected with increased fan speed. Now normally with fan speed comes noise, but not so with this implementation of the DCU II design. Much like its cousin the GTX 660Ti DCU II TOP, I was able to close up the chassis and eliminate the noise form the card with the cooling solution for the CPU being the loudest thing in the case.

ASUS' GPU Tweak utility has been revamped with features that include monitoring and tweaking, overclocking range enhancements to push the limits higher, a video recording option so that there is no need to spend money on FRAPS (that's money in your pocket if you use the feature), built-in GPU-Z reporting, and a pair of widgets. Overall it was easy to use and navigate through while testing out the functionality. Once you find you way around its a breeze. With the proliferation of gamers recording their gaming exploits and posting the content online it is all added value when you look at the cost concerns. Overall I was quite happy with the tools and how well this card overclocked.

 

Maximum Clock Speeds:

Testing for the maximum clock speed consists of looping Unigine 3.0 for 30 minutes each to see where the clock speeds fail when pushed. If the clock speed adjustment fails, then the clock speeds are adjusted and the test is rerun until each card passes the testing.

 

 

  1. Metro 2033
  2. Batman: Arkham City
  3. Battlefield 3
  4. Sid Meier's Civilization V
  5. Unigine Heaven Benchmark 3.0
  6. DiRT 3
  7. Mafia II
  8. 3DMark 11
  1. Temperature
  2. Power Consumption

Testing:

Part first-person shooter, part survival horror, Metro 2033 is based on the novel of the same name, written by Russian author Dmitry Glukhovsky. You play as Artyom in a post-apocalyptic Moscow, where you'll spend most of your time traversing the metro system, with occasional trips to the surface. Despite the dark atmosphere and bleak future for mankind, the visuals are anything but bleak. Powered by the 4A Engine, with support for DirectX 11, NVIDIA PhysX, and NVIDIA 3D Vision, the tunnels are extremely varied – in your travels, you'll come across human outposts, bandit settlements, and even half-eaten corpses. Ensuring you feel all the tension, there is no map and no health meter. Get lost without enough gas mask filters and adrenaline shots and you may soon wind up as one of those half-eaten corpses, chewed up by some horrifying manner of irradiated beast that hides in the shadows just waiting for some hapless soul to wander by.

 

Settings:

 

 

 

 

 

 

 

 

 

 

 

In this game the GTX 660 DirectCU II TOP delivers over 30 FPS both stock and overclocked with the visual quality at a high level using DX11. At four FPS behind the GTX660Ti at stock speeds and four behind the HD 7870 when overclocked it delivers playable frame rates.

Testing:

Batman: Arkham City is the sequel to Batman: Arkham Asylum released in 2009. This action adventure game based on DC Comics' Batman super hero was developed by Rocksteady Studios and published by Warner Bros. Interactive Entertainment. Batman: Arkham City uses the Unreal 3 engine.

 

Settings:

 

 

 

 

 

 

 

 

 

 

 

 

 

In Batman: Arkham City, ASUS' GTX 660 DCU II TOP is right behind the GTX 660Ti and HD 7950 in the FPS it delivers.

Testing:

Battlefield 3 is a first-person shooter video game developed by EA Digital Illusions CE and published by Electronic Arts. Battlefield 3 uses the Frostbyte 2 game engine and is the direct successor to Battlefield 2. Released in North America on October 25, 2011, the game supports DirectX 10 and 11.

Settings

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

In this game the GTX 660 is roughly five FPS faster than the HD 7870 both stock and overclocked and about 20% faster than the last generation GTX 560Ti.

Testing:

Unigine Heaven Benchmark 3.0 is a DirectX 11 GPU benchmark based on the Unigine engine. This was the first DX 11 benchmark to allow testing of DX 11 features. What sets the Heaven Benchmark apart is the addition of hardware tessellation, available in three modes – Moderate, Normal and Extreme. Although tessellation requires a video card with DirectX 11 support and Windows Vista/7, the Heaven Benchmark also supports DirectX 9, DirectX 10, DirectX 11 and OpenGL 4.0. Visually, it features beautiful floating islands that contain a tiny village and extremely detailed architecture.

 

Settings

 

 

 

 

 

 

 

 

 

 

 

 

 

In this test the GTX 660 falls a bit short of the HD 7870 both stocked and overclocked but is still significantly faster than the GTX 560Ti.

Testing:

Civilization V is a turn-based strategy game. The premise is to play as one of 18 civilizations and lead the civilization from the "dawn of man" up to the space age. This latest iteration of the Civilization series uses a new game engine and massive changes to the way the AI is used throughout the game. Civilization V is developed by Firaxis Games and is published by 2K games and was released for Windows in September of 2010. Testing will be done using actual game play with FPS measured by Fraps through a series of five turns, 150 turns into the game.

Settings

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

In this game the performance of the GTX 660 DirectCU II TOP is well above that of the HD 7870 and GTX 560Ti. With the maximum in-game settings applied the GTX 660 delivers at least 100 FPS in this game.

Testing:

DiRT 3 is the third iteration of this series. Published and developed by Codemasters, this game uses the EGO 2.0 game engine and was released in the US on PC in May of 2011.

Settings

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Much like in Civilization V, the GTX 660 DCU II is much faster than the HD 7870 in this test. At the 90+FPS level you have some hardware overhead room to enjoy this game using NVIDIA's 3D Vision system to add depth to the ride.

Testing:

Mafia II is a third-person shooter that puts you into the shoes of a poor, Sicilian immigrant, Vito Scarletta. Vito has just returned home from serving overseas in the liberation of fascist Italy, to avoiding his jail sentence, to finding his family in debt. The debt must be repaid by the end of the week, and his childhood friend, Joe Barbaro, conveniently happens to have questionable connections that he assures will help Vito clear the debt by that time. As such, Vito is sucked into a world of quick cash. Released in North America for PC in August of 2010, the game was developed by 2K Czech, published by 2K, and uses the Illusion 1.3 game engine.

 

Settings

 

 

 

 

 

 

 

 

 

 

 

 

 

The performance margin between the HD 7870 and GTX 660 DCU II TOP is three FPS in both the stock and overclocked tests.

Testing:

3DMark 11 is the next installment in Futuremark’s 3DMark series, with Vantage as its predecessor. The name implies that this benchmark is for Microsoft DirectX 11 and with an unintended coincidence, the name matches the year proceeding its release (which was the naming scheme to some prior versions of 3DMark nonetheless). 3DMark 11 is designed solely for DirectX 11, so Windows Vista or 7 are required along with a DirectX 11 graphics card in order to run this test. The Basic Edition has unlimited free tests on performance mode, whereas Vantage is only allowed for a single test run. The advanced edition costs $19.95 and unlocks nearly all of the features of the benchmark, while the professional edition runs $995.00 and is mainly suited for corporate use. The new benchmark contains six tests, four of which are aimed only at graphical testing; one to test for physics handling and one to combine graphics and physics testing together. The open source Bullet Physics library is used for physics simulation and although not as mainstream as Havok or PhysX, it still seems to be a popular choice.

With the new benchmark, comes two new demos that can be watched, both based on the tests. Unlike the tests, however, these contain basic audio. The first demo is titled "Deep Sea" and involves a few vessels exploring what looks to be a sunken U-Boat. The second demo is titled "High Temple" and presents a location similar to South American tribal ruins with statues and the occasional vehicle around. The demos are simple in that they have no story – they are really just a demonstration of what the testing will be like. The vehicles have the logos of the sponsors MSI and Antec on their sides – the sponsorships helping to make the basic edition free. The four graphics tests are slight variants of the demos. I will use the three benchmark test preset levels to test the performance of each card. The presets are used as they are comparable to what can be run with the free version, so that results can be compared across more than just a custom set of test parameters.

 

Settings

 

 

 

 

 

 

 

 

 

 

 

 

In 3DMark 11 the GTX 660 is right behind the HD 7950 in all six tests. The performance scaling from one card to the next is consistent through all six tests.

Testing:

Temperature testing will be accomplished by loading the video card to 100% using Unigine's Heaven Benchmark Version 3.0, with EVGA's Precision overclocking utility for temperature monitoring. I will be using a resolution of 1920x1080 using 8xAA and a five-run sequence to run the test, ensuring that the maximum thermal threshold is reached. The fan speed will be left in the control of the driver package and video card's BIOS for the stock load test, with the fan moved to 100% to see the best possible cooling scenario for the overclocked load test. The idle test will involve a 20-minute cool-down, with the fan speeds left on automatic in the stock speed testing and bumped up to 100% when running overclocked.

Settings

 

 

 

 

 

 

 

 

 

 

 

 

The cooling performance delivered by the GTX 660 DCU II TOP is almost 40 °C below the thermal threshold for the GK106 core when overclocked. At stock speeds the load temperatures are comparable with the GTX 560Ti yet still 10 degrees higher than the HD 7870 Flex.

Testing:

Power consumption of the system will be measured at both idle and loaded states, taking into account the peak wattage of the entire system with each video card installed. I will use Unigine's Heaven Benchmark version 3.0 to put a load onto the GPU using the settings below. A 15-minute load test will be used to simulate maximum load with the highest measured wattage value recorded as the result. The idle results will measured as the lowest wattage value recorded with no activity on the system.

Settings

 

 

 

 

 

 

 

 

 

 

 

 

 

The GTX 660 DCU II TOP delivers power consumption numbers under load that are less than the 140W TDP for the card when you look at the delta between the idle and load results. Compared to the HD 7870 Flex, the GTX 660 is more power hungry at idle and under load.

Conclusion:

After looking at the GTX 660Ti and seeing the direction NVIDIA was headed in its march to bring Kepler to the largest section of the video card market, it was interesting to see what the first swing at the market would be. What it delivered was a card that is priced in the $230 range for reference cards putting it right between the $190+ HD 7850 and $250+ HD 7870 GHz edition in both price and performance. ASUS' GTX 660 DirectCU II TOP is priced slightly higher than the $230 price point at $249. At that price you get a video card that is able to play every title I tested at greater than 30FPS using high to maximum in-game settings. Dropping the visual quality will allow higher FPS but having the ability to run the number at 1920x1080 with the eye candy on is a little more appealing for $250 or less. Adding in a 3DVision system most of the games were playable although there is a performance hit. Even so Batman had a solid 50FPS while DiRT 3 was right at 60FPS with 3DVision enabled. If you enjoy the 3D experience the GTX 660 can deliver it.

Out of the 20 performance tests run, the GTX 660 DCU II TOP was faster than the HD 7870 GHz Edition in 14 out of the 20 tests. As a percentage the GTX 660 DCU II TOP was faster in games 70% of the time. As part of the DirectCU II product stack the GTX 660 DCU II TOP delivers excellent cooling performance to go along with the gaming performance by allowing the card to run well below the thermal limits of the card with load temperature of 64 °C when the fan speed is controlled by the card's BIOS. That fact that 64 °C was attained with the fan speed running at the 10% level is pretty amazing and a testament to the design's cooling efficiency. Add in the double sealed fans as part of ASUS "Protective Design" feature set and you have a card that has the capability of outlasting that reference design cooling solution. The fans on this card are another area of improvement. Running at normal speeds and controlled by the BIOS, the fans are inaudible over the rest of the test system. Kicking the fan speed up to100% results in some whirring that is quieted down by reinstalling the side panel of the chassis.

Stock performance is great but overclocking adds performance allowing a lower end GPU to many times out perform its price point. ASUS adds in its Digi+VRM/ SAP implementation to allow the end user to have the tools to overclock the GTX 660 DirectCU II TOP to deliver that increase in performance easily and reliably. Stability and longevity are other areas addressed with the DIGI+VRM/Super Alloy Power implementation. ASUS GTX 660 DirectCU II TOP is already one of if not the fastest card from the start so overclocking margins should be on the slim side starting at a boost clock of 1137MHz. I was able to reach a solid boost clock of 1206MHz on the GK106 core used in this card with it at most times running well into the 1230MHz range in games. The memory delivered solid increases as well at 134MHz over the factory 1502MHz.

Rather than promote an aftermarket utility from another vendor, ASUS has put together its own utility called GPU Tweak. This monitoring and tweaking utility includes the ability to record your own gaming escapades to save and post online, saving you the cost of a FRAPS purchase, all for $0. As an NVIDIA-based card the GTX 660 DirectCU II TOP gets the latest feature set that comes with the Kepler architecture including Adaptive Vsync, TXAA, PhysX, SLI, and 3D Vision.

ASUS' GTX 660 DirectCU II TOP hits the performance marks set for it in convincing fashion with an expansive feature set that includes high quality components, excellent cooling, and great looks all wrapped up in the $250 price point. For 1920x1080 gaming on a budget, the GTX 660 DirectCU II TOP has the ability to leverage the right price/performance point with the latest DX11 feature set to entice gamers to make that next upgrade to enjoy all that DX11 gaming has to offer.

 

Pros:

 

Cons: