GTX 670 & 680 Clock per Clock and GPU Boost Analysis
Category : NVIDIA
Published by Christian Ney on 16.05.12
In this article we are going to analyse two things: first the clock per clock performance between the GTX 670 and GTX 680 both clocked at 1 GHz. To do so we have bypassed the GPU Boost so the graphics cards have a minimum and maximum clock frequency of 1 GHz. Second, we have raised the TDP of our GTX 670 to see how the GPU Boost will react and what it's impact on performance actually is. So let's find out what's really happening behind the scene, let there be light!





Introduction

Some of you may have noticed that from one website to another the performance of the GTX 670/680 isn't the same. It's mainly due to the GPU Boost. Wazzat? The GPU Boost has been first introduced by nVidia for the GTX 6xx series and acts like the well know Turbo clock on Intel and AMD processors. For example: the graphics processing unit of the graphics card see it's clock raising for a while until it reaches the TDP limit. However while Intel and AMD announce the Max. Turbo frequency nVidia is telling the lowest Boost frequency. This means that all nVidia cards from this series have a Max boost different but the same ''guaranteed'' Boost clock which is the official one you find in the specs and the retail box. The max boost clock maybe different from one card to another because of the manufacturing quality of the GPU, the components on the PCB and the PCB itself. For a - not that good - graphics card the TDP will be reached easily while with a very good card the TDP will be far away allowing the boost clock to go higher. In practice there is a difference in performance from one graphics card to another even if they are/look the same. We noticed that our GTX 680 sample was clocking itself up to 1097 Mhz which is 36 MHz more than the official boost frequency. While our GTX 670 Direct CU II Top was able to raise its boost clock by no less than 104 MHz from the guaranteed one: from 1'137 MHz to 1'241. Quite a boost hu? And you notice it in the performance.

So, how high does your card clock? Well it's simple, download the latest version of GPU-Z (0.6.2). Then go to the monitoring tab (sensors) and clic the GPU Clock box till it shows ''Max''. After that be sure that GPU-Z is set to refresh even in the background and launch any 3D app that is able to stress your GPU so the Boost turn on. the freqeuncy you should see in the gpu clock box match the following: ''Guaranteed Boost Clock'' + k x 13 MHz. With the Guaranteed boost clock equal to 1'059 MHz for the stock GTX 680 for exemple and k a positive integer value between 0 and 20 (let's be mad). Then you may ask why 13 MHz ? Well it seems that the boost clock is working in 13 Mhz increments that we are going to call ''steps''.

It is now a fact, that not all test you can read in the Internet were performed under standard conditions. Therefore there sometimes is quite a big measurement error. Following we wanted to measure the performance impact by making several testing scenario.

First of all a comparison clock per clock GTX 670 against her big sister the GTX 680. The the only difference between the two card will be only the amount of shaders available in the core as all the other specs are exactly the same. For the record the GTX 680 has 1'536 shaders while the GTX 670 gets 1'344.

In the second scenario we are going to measure the performance between a reference GTX 680 and a reference GTX 670. Assuming that the average GTX 680 GPU have a 2 steps greater Boost, ie an increase of 26 MHz over the guaranteed frequency boost we made sure that our card match this during our test. For the GTX 670 is a bit different. Using the GTX 670 DirectCU II we're going to simulate a reference GTX 670. Usually this card increases clocks by 78 MHz.

Last but not least a fight between our GTX 670 Direct CU II Top against herself. With the only difference is that we raised the TDP in one case. Thanks to the option (Power Target) that is available in the app GPU Tweak from Asus (Also available in the softwares from other brands such as MSI AfterBurner and EVGA Precision X) that allows the graphics card to clock the max turbo higher... or not! We will discuss this point in the conclusion.

Huho finally it's not finished. We decided at the last minute to add one more scenario. What if you are as lucky as Donald is? The GTX 670 you just bought doesn't go further than the official boost frequency. In this case you will see how such a bad GTX 670 will perform against a GTX 680. Both cards have been clocked so they don't clock themselves higher than their official boost frequency.

Following you will find a summary regarding the clock frequencies we tested. The test setup and some GPU-Z screenshots can be found on Page 2. While on page 3 & 4 you will find the synthetic benchmarks results. The ingame performances can be found on page 5 to 8. En finally on page 9 we made a summary (average performance) of all results and page 10 there is a little conclusion. Enjoy!





What we tested GPU Clock Memory Clock GPU Boost Clock (Min.) Max. GPU Boost Clock
GTX 680 1GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
GTX 670 1 GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
         
GTX 680 Ref (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'097 MHz
GTX 670 Ref (FW301.25) 915 MHz 1'502 MHz 980 MHz 1'058 MHz 
         
GTX 670 DCU II Top (TDP 117 %) (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
GTX 670 DCU II Top (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
         
GTX 680 Turbo Max = 1'059 MHz (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'059 MHz
GTX 670 Turbo Max = 980 MHz (FW301.25) 915 Mhz 1'502 MHz 980 MHz 980 MHz



Page 1 - Introduction Page 6 - Call of Duty: Modern Warfare 3 / BattleField 3
Page 2 - Test Setup Page 7 - Crysis 2 / Dragon Age 2 / S.T.A.L.K.E.R.
Page 3 - 3D Mark 11 / 3D Mark Vantage Page 8 - The Elder Scrolls V: Skyrim / StarCraft II
Page 4 - Unigine Heaven / TessMark Page 9 - Summary Benchmark Results
Page 5 - Alien vs. Predator / Batman: Arkham City / Dirt 2 Page 10 - Conclusion



Discuss this article in the forums [pagebreak]

Test Setup

Hardware

Mainboard
  • ASUS P8P67 Pro (BIOS 2303)
CPUs
  • Intel Core i7-2600K @ 3.4 GHz (Turbo Off / HT On)
Memory
  • G.Skill RipjawsZ Dual Channel 4x4GB CL9-9-9-24-DDR3-1600 MHz
Graphic Cards (Driver)
  • nVidia GeForce GTX 680 (ForceWare 301.25)
  • ASUS GeForce GTX 670 DCU II Top (ForceWare 301.25)
HDD
  • Samsung SSD 830 Series 128 GB
PSU
  • Seasonic Platinum SS-1000XP / 1000 Watts


GTX 670 1 GHz vs GTX 680 1 GHz

   

GTX 670 vs GTX 680

   

ASUS GTX 670 DirectCU II Top


GTX 670 980 MHz vs GTX 680 1'059 MHz

   



Page 1 - Introduction Page 6 - Call of Duty: Modern Warfare 3 / BattleField 3
Page 2 - Test Setup Page 7 - Crysis 2 / Dragon Age 2 / S.T.A.L.K.E.R.
Page 3 - 3D Mark 11 / 3D Mark Vantage Page 8 - The Elder Scrolls V: Skyrim / StarCraft II
Page 4 - Unigine Heaven / TessMark Page 9 - Summary Benchmark Results
Page 5 - Alien vs. Predator / Batman: Arkham City / Dirt 2 Page 10 - Conclusion



Discuss this article in the forums [pagebreak]

3DMark 11





What we tested GPU Clock Memory Clock GPU Boost Clock (Min.) Max. GPU Boost Clock
GTX 680 1GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
GTX 670 1 GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
         
GTX 680 Ref (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'097 MHz
GTX 670 Ref (FW301.25) 915 MHz 1'502 MHz 980 MHz 1'058 MHz 
         
GTX 670 DCU II Top (TDP 117 %) (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
GTX 670 DCU II Top (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
         
GTX 680 Turbo Max = 1'059 MHz (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'059 MHz
GTX 670 Turbo Max = 980 MHz (FW301.25) 915 Mhz 1'502 MHz 980 MHz 980 MHz


3DMark Vantage






Page 1 - Introduction Page 6 - Call of Duty: Modern Warfare 3 / BattleField 3
Page 2 - Test Setup Page 7 - Crysis 2 / Dragon Age 2 / S.T.A.L.K.E.R.
Page 3 - 3D Mark 11 / 3D Mark Vantage Page 8 - The Elder Scrolls V: Skyrim / StarCraft II
Page 4 - Unigine Heaven / TessMark Page 9 - Summary Benchmark Results
Page 5 - Alien vs. Predator / Batman: Arkham City / Dirt 2 Page 10 - Conclusion



Discuss this article in the forums [pagebreak]

Unigine Heaven




What we tested GPU Clock Memory Clock GPU Boost Clock (Min.) Max. GPU Boost Clock
GTX 680 1GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
GTX 670 1 GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
         
GTX 680 Ref (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'097 MHz
GTX 670 Ref (FW301.25) 915 MHz 1'502 MHz 980 MHz 1'058 MHz 
         
GTX 670 DCU II Top (TDP 117 %) (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
GTX 670 DCU II Top (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
         
GTX 680 Turbo Max = 1'059 MHz (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'059 MHz
GTX 670 Turbo Max = 980 MHz (FW301.25) 915 Mhz 1'502 MHz 980 MHz 980 MHz



TessMark






Page 1 - Introduction Page 6 - Call of Duty: Modern Warfare 3 / BattleField 3
Page 2 - Test Setup Page 7 - Crysis 2 / Dragon Age 2 / S.T.A.L.K.E.R.
Page 3 - 3D Mark 11 / 3D Mark Vantage Page 8 - The Elder Scrolls V: Skyrim / StarCraft II
Page 4 - Unigine Heaven / TessMark Page 9 - Summary Benchmark Results
Page 5 - Alien vs. Predator / Batman: Arkham City / Dirt 2 Page 10 - Conclusion



Discuss this article in the forums [pagebreak]

Alien vs Predator





Batman: Arkham City




What we tested GPU Clock Memory Clock GPU Boost Clock (Min.) Max. GPU Boost Clock
GTX 680 1GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
GTX 670 1 GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
         
GTX 680 Ref (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'097 MHz
GTX 670 Ref (FW301.25) 915 MHz 1'502 MHz 980 MHz 1'058 MHz 
         
GTX 670 DCU II Top (TDP 117 %) (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
GTX 670 DCU II Top (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
         
GTX 680 Turbo Max = 1'059 MHz (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'059 MHz
GTX 670 Turbo Max = 980 MHz (FW301.25) 915 Mhz 1'502 MHz 980 MHz 980 MHz



DIRT 2






Page 1 - Introduction Page 6 - Call of Duty: Modern Warfare 3 / BattleField 3
Page 2 - Test Setup Page 7 - Crysis 2 / Dragon Age 2 / S.T.A.L.K.E.R.
Page 3 - 3D Mark 11 / 3D Mark Vantage Page 8 - The Elder Scrolls V: Skyrim / StarCraft II
Page 4 - Unigine Heaven / TessMark Page 9 - Summary Benchmark Results
Page 5 - Alien vs. Predator / Batman: Arkham City / Dirt 2 Page 10 - Conclusion



Discuss this article in the forums [pagebreak]

Call of Duty Modern Warfare 3




What we tested GPU Clock Memory Clock GPU Boost Clock (Min.) Max. GPU Boost Clock
GTX 680 1GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
GTX 670 1 GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
         
GTX 680 Ref (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'097 MHz
GTX 670 Ref (FW301.25) 915 MHz 1'502 MHz 980 MHz 1'058 MHz 
         
GTX 670 DCU II Top (TDP 117 %) (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
GTX 670 DCU II Top (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
         
GTX 680 Turbo Max = 1'059 MHz (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'059 MHz
GTX 670 Turbo Max = 980 MHz (FW301.25) 915 Mhz 1'502 MHz 980 MHz 980 MHz



BattleField 3






Page 1 - Introduction Page 6 - Call of Duty: Modern Warfare 3 / BattleField 3
Page 2 - Test Setup Page 7 - Crysis 2 / Dragon Age 2 / S.T.A.L.K.E.R.
Page 3 - 3D Mark 11 / 3D Mark Vantage Page 8 - The Elder Scrolls V: Skyrim / StarCraft II
Page 4 - Unigine Heaven / TessMark Page 9 - Summary Benchmark Results
Page 5 - Alien vs. Predator / Batman: Arkham City / Dirt 2 Page 10 - Conclusion



Discuss this article in the forums [pagebreak]

Crysis 2





Dragon Age 2




What we tested GPU Clock Memory Clock GPU Boost Clock (Min.) Max. GPU Boost Clock
GTX 680 1GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
GTX 670 1 GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
         
GTX 680 Ref (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'097 MHz
GTX 670 Ref (FW301.25) 915 MHz 1'502 MHz 980 MHz 1'058 MHz 
         
GTX 670 DCU II Top (TDP 117 %) (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
GTX 670 DCU II Top (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
         
GTX 680 Turbo Max = 1'059 MHz (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'059 MHz
GTX 670 Turbo Max = 980 MHz (FW301.25) 915 Mhz 1'502 MHz 980 MHz 980 MHz



S.T.A.L.K.E.R. Call of Pripyat






Page 1 - Introduction Page 6 - Call of Duty: Modern Warfare 3 / BattleField 3
Page 2 - Test Setup Page 7 - Crysis 2 / Dragon Age 2 / S.T.A.L.K.E.R.
Page 3 - 3D Mark 11 / 3D Mark Vantage Page 8 - The Elder Scrolls V: Skyrim / StarCraft II
Page 4 - Unigine Heaven / TessMark Page 9 - Summary Benchmark Results
Page 5 - Alien vs. Predator / Batman: Arkham City / Dirt 2 Page 10 - Conclusion



Discuss this article in the forums [pagebreak]

The Elder Scrolls V: Skyrim




What we tested GPU Clock Memory Clock GPU Boost Clock (Min.) Max. GPU Boost Clock
GTX 680 1GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
GTX 670 1 GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
         
GTX 680 Ref (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'097 MHz
GTX 670 Ref (FW301.25) 915 MHz 1'502 MHz 980 MHz 1'058 MHz 
         
GTX 670 DCU II Top (TDP 117 %) (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
GTX 670 DCU II Top (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
         
GTX 680 Turbo Max = 1'059 MHz (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'059 MHz
GTX 670 Turbo Max = 980 MHz (FW301.25) 915 Mhz 1'502 MHz 980 MHz 980 MHz



StarCraft II






Page 1 - Introduction Page 6 - Call of Duty: Modern Warfare 3 / BattleField 3
Page 2 - Test Setup Page 7 - Crysis 2 / Dragon Age 2 / S.T.A.L.K.E.R.
Page 3 - 3D Mark 11 / 3D Mark Vantage Page 8 - The Elder Scrolls V: Skyrim / StarCraft II
Page 4 - Unigine Heaven / TessMark Page 9 - Summary Benchmark Results
Page 5 - Alien vs. Predator / Batman: Arkham City / Dirt 2 Page 10 - Conclusion



Discuss this article in the forums [pagebreak]

Benchmark Summary

Synthetic Benchmarks




What we tested GPU Clock Memory Clock GPU Boost Clock (Min.) Max. GPU Boost Clock
GTX 680 1GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
GTX 670 1 GHz (FW301.25) 1'000 MHz 1'502 MHz 1'000 MHz 1'000 MHz
         
GTX 680 Ref (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'097 MHz
GTX 670 Ref (FW301.25) 915 MHz 1'502 MHz 980 MHz 1'058 MHz 
         
GTX 670 DCU II Top (TDP 117 %) (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
GTX 670 DCU II Top (FW301.25) 1'059 MHz 1'502 MHz 1'137 MHz 1'241 MHz
         
GTX 680 Turbo Max = 1'059 MHz (FW301.25) 1'006 MHz 1'502 MHz 1'059 MHz 1'059 MHz
GTX 670 Turbo Max = 980 MHz (FW301.25) 915 Mhz 1'502 MHz 980 MHz 980 MHz



Games






Page 1 - Introduction Page 6 - Call of Duty: Modern Warfare 3 / BattleField 3
Page 2 - Test Setup Page 7 - Crysis 2 / Dragon Age 2 / S.T.A.L.K.E.R.
Page 3 - 3D Mark 11 / 3D Mark Vantage Page 8 - The Elder Scrolls V: Skyrim / StarCraft II
Page 4 - Unigine Heaven / TessMark Page 9 - Summary Benchmark Results
Page 5 - Alien vs. Predator / Batman: Arkham City / Dirt 2 Page 10 - Conclusion



Discuss this article in the forums [pagebreak]

Conclusion

1rst Scenario: Clocked at the same frequency there is a gap of almost 10 % in performance between the GTX 670 and the GTX 680 in theoretical benchmarks such as 3D Mark 11. While in games this is another thing, we noticed only 3 % difference in this case, nothing to worry about I would say. The reason for thise differences can be found in the specs of the card. The GTX 680 simply has 192 more shaders than the GTX 670.

2nd Scenario: this one shows Almost the same like in the first scenario. You will only notice a big difference in synthetic benchmarks rather than with games where the difference in performance is low. For the record: at this point we have benched the cards like if they were under normal use.

3rd Scenario: We noticed that when you raise the TDP limit of the graphics card it will operate always at the max boost clock. For exemple our sample was always running at 1'241 MHz. No less than 104 Mhz higher than the official boost clock. From ''always at'' 1'241 Mhz and up to 1'241 MHz the performance gap is very low and you almost don't see it in games.

4th and last Scenario: Wow, in this situation where the cards don't have any Turbo there is quite a difference in both synthetic benchmarks and games. In fact it is 8 % and 15 % more performance for the GTX 680 on the GTX 670.

Conclusion: the GTX 670 gives the GTX 680 an hard time. Unless you have a banker neighbor we don't see why one should spend 120 - 150 Euros (est. CHF 144.- up to 180.-) more on a graphics card that performs almost the same in games. If you like to run synthetic benchmarks, like me, then you have a point and a real problem (just like me)!
Meanwhile we prefer to spend 20 - 50 more bucks on a GTX 670 that comes with a custom PCB, a factory overclocking and a better cooling system than nVidia's one. In this case you are just winning on all sides, performance, noise level and design at a lower price and power consumption.




Page 1 - Introduction Page 6 - Call of Duty: Modern Warfare 3 / BattleField 3
Page 2 - Test Setup Page 7 - Crysis 2 / Dragon Age 2 / S.T.A.L.K.E.R.
Page 3 - 3D Mark 11 / 3D Mark Vantage Page 8 - The Elder Scrolls V: Skyrim / StarCraft II
Page 4 - Unigine Heaven / TessMark Page 9 - Summary Benchmark Results
Page 5 - Alien vs. Predator / Batman: Arkham City / Dirt 2 Page 10 - Conclusion



Discuss this article in the forums