NVIDIA GTX 670 Review

ccokeman - 2012-05-05 19:54:41 in Video Cards
Category: Video Cards
Reviewed by: ccokeman   
Reviewed on: May 10, 2012
Price: $399


At this point NVIDIA is pumping out video cards based on the successful Kepler GK104 core with the launch of the GTX 690, GTX 680 and now the GTX 670, which is targeting the more middle of the road gamers. We saw that the GTX 680 was a potent product from the start that handed AMD's king of the hill single GPU Southern Islands-based HD 7970 a losing hand in just about every game and resolution tested. The GTX 680 proved to be cooler running and more power efficient, and directly caused a dynamic shift in the performance playing field when the price point was lower at retail than the HD 7970 was selling for. AMD countered with price drops to make the HD 7970 more competitive from a price for performance perspective. Now NVIDIA is going to go for the jugular with the launch of the GTX 670 and really drive the price performance ratio back to the green side of the fence, with the HD 7950 square in its sights.

The mantra for NVIDIA is to run cooler, more efficiently and deliver exceptional gaming performance; things it proved with the last two launches. By using the same SMX architecture (albeit one less SMX), the GTX 670 is supposed to be between 30% to 50% faster than the GTX 570 across a wide range of games. This makes a perfect time to upgrade for the person on that traditional (or seemingly so) three year upgrade cycle. Upgrading from a GTX 470 the user should see results up to twice as fast per the press release. We have seen what the last two GK104 cards are capable of, now let's see if NVIDIA can knock this one straight out of the park with a price point that will make the GTX 670 all the more appealing.

Closer Look:

The packaging for the GTX 670 was nowhere near as special as the GTX 690 but is more indicative of a retail box seen at big box retailers. The black box has the NVIDIA logo embossed on the cover to identify what brand is inside. Standard retail packaging follows through the interior with a box for the accessories and the obligatory anti-static bag.












The GTX 670 uses the same 28nm Kepler SMX architecture introduced on the GK104-based GTX 680. The GPU consists of a series of GPCs (Graphics Processing Clusters), four in this case, on each GK104 with two SMX units each with 192 cores for a total of 1536 CUDA cores per GPU core when used on the GTX 680. The GTX 670 has had one of the eight SMX disabled effectively dropping the CUDA core count to 1344. To more effectively manage power consumption, the traditional method of running the shader clock at twice the core clock was abandoned and now the clock speeds run at a 1:1 ratio. Each GPC has a single raster engine and dynamically share 1MB of L2 cache. The GPU core features 112 texture units and 32 ROPs on the GTX 670. A new feature with GK104 is hardware and software-based GPU Boost technology, which dynamically boosts the clock speeds of the GPU cores when there is available TDP headroom, much like the latest CPUs from Intel and AMD. The base clock speeds for the GTX 670 are 915MHz with a GPU Boost core clock speed of around 980MHz. The GTX 670 memory subsystem is the same as that used on the GTX 680 with four 64-bit (256-bit) memory controllers handling 2GB of GDDR5 memory running at 1500MHz (6000MHz effective). To put it in simple terms, the GTX 670 is a GTX 680 with only seven SMX units.


While the reference board is fully capable of handling some spirited overclocking, NVIDIA's board partners, like ASUS, Galaxy, EVGA, Zotac, Gainward and more, will have a variety of factory overclocked offerings with their own custom PCBs. Below are a few mages that show off a few of these new cards.




Even though knowing what's going to be under the skin, we need to take a look at the GTX 670 from NVIDIA.

Closer Look:

What we have is the reference board equipped GTX 670 from NVIDIA. From the front the card looks similar to the GTX 680 but from the back you will notice that it is quite different. The PCB does not run the length of the entire video card. A smaller PCB was used that measures 6.5 inches in length with overall card length at 9.5 inches. This shrink in size allows the card to fit in a larger variety of chassis. The blower style fan vents the thermal load out of the chassis to promote better component cooling in smaller form factor chassis. The GEFORCE GTX logo on the top side of the fan shroud looks good but sadly does not light up like the logo on the GTX 690.















Connectivity options for the GTX 670 include a pair of Dual Link DVI ports, a full size DisplayPort 1.2 port and an HDMI 1.4a port to connect up to four monitors simultaneously. NVIDIA Surround is supported on the GTX 670 in a 3+1 configuration. The venting on the mounting bracket is used to vent the thermal load out of the shroud on the GTX 670. The trend has been to enlarge these vents to reduce back pressure and noise from the cooling fan. The back end of the card is closed up completely without any intake channels so all of the air comes through the fan opening in the shroud.


There are two SLI brdge connections on the GTX 670 allowing SLI configurations of more than two cards. With the GTX 670 a second card is not needed to enjoy NVIDIA Surround as it can handle this with just a single card. Power requirements include two 6-pin PEG power connections. The TDP is 170W with a minimum power supply requirement of 500 watts. NVIDIA has enabled a feature that lets the end user know when one of the 6-pin power connectors is not inserted correctly with a warning on the screen that tells the user to check the power connections. The reasoning behind this is that one of its top support issues comes down to simple basic installation mistakes in not putting in the power connector fully.


Pulling off the shroud we can get in and see what kind of cooling solution that is employed on the GTX 670. A small copper-based heat sink with nickel-plated fins is used on the GPU core and a small aluminum sink is used on the VRM circuit. The blower fan is attached to the mini-me sized PCB with a pair of screws and extends the length of the card out by three inches. To help reduce noise from the blower fan an acoustic dampening material is used to eliminate unwanted tones. The mini-me sized PCB was a surprise initially but as it turns out the GPU is efficient enough to move the power circuit to the left side of the board by rotating the GK104 core. By rotating the core and moving the power circuits there is an increase in power integrity and efficiency. With the power circuit no longer on the right side of the PCB it was removed saving on cost of goods and allowing a smaller overall card.


The GTX 670 is built around the GK104 Kepler core. As a scalable, modular-type core much like the Fermi micro-architecture, individual SMX units can be removed to downsize to fit a performance point. The GTX 670 has a total of 3.54 Billion transistors and is equipped with four GPC (Graphics Processing Cores) with seven SMX instead of the eight on the GTX 680, which drops the CUDA core count to 1344. Like the GTX 680, the GTX 670 has 32 ROPs but only 112 Texture units. Clock speeds are similar to the GTX 680 at 915MHz with a GPU Boost clock of 980MHz, although I saw much higher in my testing. The memory subsystem remains unchanged from that of the GTX 680 with four 64-bit (256-bit) memory controllers. 2GB of GDDR5 memory is used on board clocked at 1502MHz (6008MHz QDR). The memory used on the GTX 670 is from Hynix with part number H5GQ2H24AFR-R0C.


With that quick look at the GTX 670 and what's under the hood let's take a look at all it has to offer in terms of performance and value.


Graphics Processing Clusters
Streaming Multiprocessors
CUDA Cores
Texture Units
ROP Units
Base Clock
915 MHz
Boost Clock
980 MHz
Memory Clock
6008 MHz
L2 Cache Size
Total Video Memory
2048MB GDDR5
Memory Interface
Total Memory Bandwidth
192.2 GB/s
Texture Filtering Rate (Bilinear)
102.5 GigaTexels/sec
Fabrication Process
28 nm
Transistor Count
3.54 Billion
2 x Dual-Link DVI
1 DisplayPort
Form Factor
Dual Slot
Power Connectors
2x 6-pin
Recommended Power Supply
500 Watts
Thermal Design Power (TDP)
170 Watts
Thermal Threshold
98 °C




All information courtesy of NVIDIA


Testing of the NVIDIA GTX 670 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 690,  GTX 680 and the GTX 670. Other NVIDIA comparison cards will be using the 296.10 drivers; AMD will be using Catalyst 12.3 drivers.


Comparison Video Cards:



Overclocking a Kepler-based GPU is somewhat different from what we have been used to with prior generation NVIDIA video cards. Or for that matter any video card. While you still have to raise the clock speed, voltage and memory clocks, how they are applied is where the difference comes into play. NVIDIA uses GPU Boost to dynamically raise the clock speeds under load to increase performance as high as possible while still falling into the thermal (98C) and power design (300 watt) envelopes. If you have had fun overclocking a Sandy Bridge-based CPU from Intel you kind of get the gist of how it all works. NVIDIA uses both a hardware and software-based set of controls to ensure thermal and power envelopes are not exceeded while still allowing the highest possible performance. The baseline clock speed of 915MHz is used when the most demanding games are played yet in every game I tested the clock speed was usually above the 980MHz GPU Boost clocks for the majority of the test. It seems as though the controls used by NVIDIA seem to allow this kind of speed at will.

Raising the performance levels of the GTX 670 requires using a software-based utility such as EVGA Precision or MSI Afterburner to raise the GPU core and memory clocks, the power target limits, core voltage and the fan speed. Using all of these tools is going to be required to get the most from the Kepler GPU. After getting my legs wet on the GTX 690 I went straight for the top rather than inching the clock speeds up and set the power target to the 122% maximum level; boosting the clock speed to +153MHz on the core and +265 on the memory and bumping the core voltage to +1175mv. Then turned on Unigine 3.0 with all settings maxed out with a resolution of 5760x1080 to check stability. About two minutes in the familiar fan speed crash and black screen told me that was a little aggressive for this card. After a restart and applying the same setting and clock speeds I made a change to the GPU core clock speed and dropped it to +147 and dropped the voltage to +1150mv and reran the tests with success.

Now at a lower resolution a higher clock speed was possible but my testing includes resolutions up to 5760x1080 and the clock speeds have to be stable up to that level. The GTX 670, when run at the default speed setting, showed a nice increase in clock speed above the 980MHz GPU Boost clock speed in many games with as high as 1097MHz on the GPU core or 100MHz over the default boost clock. This is because the GPU was staying underneath the 100% power target. Still a clock speed of 1231MHz (as high as 1245MHz) is over 300Mhz faster than the base clock speed on the GK104 core and 138MHz higher on the GDDR5 memory (6552MHz QDR). When running through the benchmark suite with the GTX 670 overclocked we saw measurable gains in performance across the board in each game tested.


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


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.














The performance of the GTX 670 is outstanding in Metro 2033. It delivers FPS above 30 FPS at 5760x1080 both stock and overclocked and outperforms the higher priced HD 7970 in three out of four resolution tests.


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.
















In Batman: Arkham City the GTX 670 delivers excellent results in comparison to the AMD cards and previous generation NVIDIA cards.


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.

















At 1920x1080 the GTX 670 delivers FPS results just under the GTX 680 and ahead of the HD 7970 both stock and overclocked. At 5760x1080 the performance falls to between the HD 7970 and HD 7950 at stock speeds and more or less identical to them at 41FPS when all of the cards are overclocked. Pretty solid results for a card that costs less than AMD's top-end single GPU card.


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.
















At 1920x1080 in the stock speed testing the GTX 670 delivers performance equal to the factory overclocked HD 7970. When overclocked the HD 7970 and HD 7950 delivers a slightly higher level of performance. The GTX 670 runs out of steam when the settings are maxed out at 5760x1080.


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.

















In this game the performance falls off at the highest resolution.


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.



















DiRT 3 performance has the GTX 670 just above the HD 7970 and HD 7950 at 1920x1080 and about even at 5760x1080.


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.
















Performance in this game is close to that of the HD 7970 at 1920x1080 and well above what AMD has to offer when you move to a three screen setup. The 5760x1080 resolution is where the GTX 670 is the stronger performer.


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.













In 3DMark 11 the GTX 670 outperforms AMD's HD 7970 and HD 7950 in all six tests.


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.













Cooling on the GTX 670 is indicative of the power efficiency by the smallish heat sink used to manage the thermal load. It does well enough to keep the GPU well below its 98C thermal threshold. NVIDIA has worked to reduce the noise signature of the fan by incorporating an acoustic dampening material and rewriting the fan speed control algorithms so there is a linear increase in fan speed rather than ratcheting up in large steps.


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.














The GTX 670 delivers power numbers to suggest that the 170W usage rating in games is spot on with a delta of 166W at stock speeds and 174W when overclocked.


After having looked at both the GTX 690 and GTX 680 and now the GTX 670, it is clearly evident that Kepler-based GPUs deliver a higher level of gaming performance than the competition at a better price point. Priced at $399 it is equal to or less expensive than HD 7950 offerings at more than a few etailers. Sure you can find bargains with rebates but for the most part the $399 price point is at the low end for an HD 7950. HD 7970s are still at the $499 price point. Why is this such a big deal? Well the NVIDIA GTX 670 cleans house with the HD 7950 in just about every benchmark and game tested. There are a few wins for the HD 7950 at 5760x1080, but at 1920x1080 where most players will be gaming, it's a no win situation. What's even more impressive is that in the majority of tests it beat out AMD's $499 single GPU powerhouse HD 7970, all the while using less power and running cooler. Both of these bonuses can't be overstated since you won't have to mortgage the kids' futures to pay the power bill for your gaming fix. As impressed as I was with the GTX 690, the GTX 670 is even more impressive because it takes a Kepler GK104 with one less SMX and delivers performance levels almost on par with the GTX 680.

The cooling solution used is adequate for the task of cooling down the GPU and memory and is the same one used on the GTX 680. Temperatures were very close to what the GTX 690 delivered all the way around without the noise penalty associated with previous generation cards. When overclocking the GTX 670 the maximum fan speed I could set in the EVGA Precision application was 80%. At this level the fan was audible inside the chassis if you listened for it. If the card BIOS controls the fan speeds, the maximum it would ramp up to with the temperatures delivered was 53%. For all intents and purposes this is dead silent. Overclocking the GTX 670 is a way to gain additional FPS performance. NVIDIA does this dynamically for the end user up to a point with its GPU Boost technology. On this card the stock clock speed on the GPU is 915MHz with a boost speed of 980MHz. It was rare in my testing to see a boost clock as low as 980MHz as I found it to be much closer to 1100MHz in just about every game I tested. Not just close as in 25MHz away, but I saw 1097MHz using the stock voltage and fan speed. That's a 182MHz boost without even doing anything but playing a game. Adding clock speed to the GPU and memory were easy enough with EVGA Precision or the latest version of MSI Afterburner. The final clock speeds for this card were 1230MHz on the GPU and 1638MHz (6552MHz QDR). Overclocking drives the performance up quite nicely in all the games and benchmarks tested with a score of almost P10000 in 3DMark 11.

The GTX 670 proves that you do not need the highest dollar video card on the market to enjoy a surround gaming experience with framerates above 30FPS. If you need more you can always step up to a second card for a smooth running SLI setup for an even higher level of performance and FPS scaling with the eye candy turned up. Adding a 3DVision 2 setup to the scenario provides a more engaging game experience, but as a single card 3D Surround is going to be a little hard on the hardware as there is some overhead with the addition of the 3DVision setup. At 1920x1080 you can turn up the settings ,including PhysX with 3DVision, to get the most visually stimulating gaming. Adaptive VSync is a new feature for the Kepler line up and is used to manage VSync by dynamically turning VSync on and off to minimize frame tearing and reduce stuttering. FXAA and TXAA are implemented with the Kepler lineup to improve texture aliasing without the overhead associated with MSAA.

We spoke with NVIDIA who assured us we will see plenty of stock available on the GTX 670. We really hope so, considering the GTX 680 is hard to find. We asked NVIDIA why there was a shortage and the company told us because it was selling so well. We decided to make some inquires to some big retailers to see what they said, and the response was the GTX 680 is outselling the 7970 by as much as four to one. That is pretty scary when you think about it; great for NVIDIA but bad for us who have slow Internet connections that can't buy quick enough.

What this all boils down to is that NVIDIA has delivered a wicked fast card in the $399 price point that will essentially deliver the highest FPS performance per dollar spent. As an upgrade for the gamer who has been sitting on a GTX 470 this card is a great upgrade path and offers up a whole new level of gaming performance. No need to stop at the GTX 570 when you can get this kind of bang for the buck. The GTX 670 is a cool running, efficient card capable of delivering a high level of performance with the added bonus of being able to use the entire NVIDIA ecosystem. It's fast, its frugal on power and it's quiet. Just what the doctor ordered. Kepler continues to perform very well and we are excited to see what is next from the green camp. As for the GTX 670, it's better than make-up sex in the morning. :)