Overclocking a Pascal GPU - How GPU Boost 3 works
Thanks to Nvidia GPU Boost 3, all Pascal cards automatically increase their core clock, and many of them are able to reach 1,900 - 2,000 MHz on their own.
How GPU Boost 3 works
The MHz increase produced by GPU Boost 3 depends on the temperature of your video card. The best results are attained at around 60 degree celsius.
It requires no configuration.
It only increases the core clock, not the memory one.
Before trying to manually increase the core clock, test your fan speed to understand if the card will self-overclock with better temps. Usually, you can reach 1,900 - 2,000 MHz easily if the card has a good cooler or if you don’t mind the noise.
Once reaching the maximum clock possible with GPU Boost, it is time to overclock the card in the traditional way to step up the core even more, and to work on the memory clock.
How to manually overclock the GPU
Run Heaven in windowed mode. It will be simpler to work on MSI simultaneously.
1. Download Unigine Heaven Benchmark - It's free.
2. Download MSI Afterburner. You don’t need a MSI card to use it.
3. Max the sliders of Power Limit and Temp Limit. It gives your card more room to work with, and can’t cause any harm as long as your temperatures are safe.
4. Open Heaven. I recommend using the windowed mode.
How to find your maximum Core Clock
5. On MSI, add +50 to Core Clock and test Heaven for at least one minute. If there are no artifacts or crashes, add 50 more and keep testing.
6. If it crashes or there are artifacts, reduce it by 25, until you are stable. Test for a few minutes.
Your temperature could greatly increase due to the overclock, and past a certain limit, the GPU Boost becomes unstable and reduces your maximum clock.
Anything after 2,000 - 2,100 MHz depends on luck. For example, even with a temperature of only 61 degree celsius, my card can’t go past 2,125 without displaying artifacts.
How to find your maximum Memory Clock
7. Run Heaven and pause it at any point.
8. Check the fps, it should be stable with slight variations of 1-3.
9. On MSI, add +100 to Memory Clock. The fps will marginally rise.
10. Keep adding +100. At a certain point the fps will stop rising and even drop: it is due to the memory error correction. The GPU probably won’t display artifact neither crash, but you will lose fps because the memory clock is unstable.
11. Decrease it by 50 or 100 until you reach your last highest fps. Test for a few minutes.
After identifying your final core and memory clocks, save a profile on MSI Afterburner, click “Apply overclocking at system startup”, and configure the software in the general options to automatically start with Windows.
Check your memory type with GPU-Z
Most Pascal cards have Samsung memory modules that will easily overclock for 400-600+ MHz. Some cards have Micron modules that often have problems even with small 100-300 MHz overclocks.
Use GPU-Z to check which ones your card is using. Many manufacturers released an updated VBIOS to fix some of the overclocking issues with the Micron modules.
Extra tips
GPU-Z tells you what’s holding back your overclock. Goloith, a reader of my blog - where this article was originally posted - shared this info.
Go at the bottom of the second page of GPU-Z - Sensors tab -> PerfCap Reason. You will notice one of these three colors:
Grey: Software limited. You haven't overclocked enough with the sliders.
Blue: Voltage limited. A common issue with Pascal.
Green: Power limited. This can happen frequently to 1080TI FE in certain games. You can avoid this issue by undervolting your card.
Undervolting. You can improve your temperatures, save energy, and often even get a slightly better overclock by undervolting your GPU. Though it is fairly simple, still would not suggest this method for those who do not have experience tinkering with their PC.
A stressing benchmark. Heaven is a good benchmark, but not the most demanding one. If you want to stress your GPU even more, Superposition Benchmark is a great choice. For stress testing, run Superposition in "Game Mode" and then select "Cinematic Mode" at the top-left.
Header Image: Nvidia logo
