Overclocking GeForce GTX 980 SLI x3
Overclocking GeForce GTX 980 SLI x3
As most of you know, with most video cards you can apply a simple series of tricks to boost the overall performance a little. Typically you can tweak on core clock frequencies and voltages.
What Do We Need?
One of the best tools for overclocking Nvidia and AMD videocards is our own AfterBurner which will work with 90% of the graphics cards out there. We can really recommend it, download here.
Where Should We Go?
Overclocking: By increasing the frequency of the videocard's memory and GPU, we can make the videocard increase its calculation clock cycles per second. It sounds hard, but it can really be done in less than a few minutes. I always tend to recommend to novice users and beginners, to not increase the frequency any higher than 5% on the core and memory clock. Example: If your card runs at 600 MHz (which is pretty common these days) then I suggest that you don't increase the frequency any higher than 30 to 50 MHz. More advanced users push the frequency often way higher. Usually when your 3D graphics start to show artifacts such as white dots ("snow"), you should back down 25 MHz and leave it at that. Usually when you are overclocking too hard, it'll start to show artifacts, empty polygons or it will even freeze. Carefully find that limit and then back down at least 20 MHz from the moment you notice an artifact. Look carefully and observe well.
All in all... tweaking GPUs is at your own risk!
| Original GTX 980 | This sample | Overclocked |
| Core Clock: 1126 MHz | Core Clock: 1126 MHz | Core Clock 1276 MHz |
| Boost Clock: 1216 MHz | Boost Clock: 1216 MHz | Boost Clock: 1416~1428 MHz |
| Memory Clock: 7000 MHz | Memory Clock: 7000 MHz | Memory Clock: 7908 MHz |
The 2nd example is overclocking with the three 980 reference cards. With AfterBurner we applied:
- CPU clock +150 MHz
- Power limiter 122%
- Mem clock +450 MHz
- Volatge + 87 Mv
- FAN RPM 80% (a bit noisy)
Now first I like you to spend a minute and look at the screenshot above, I charted some important stuff here. Overclocking with 3-way SLI should be more complicated as we have two reference cards and one G1 gaming (factory overclocked card) from Gigabyte.
However, overclocking could not be any easier as Nvidia has SLI sync limiters these days, basically you overclock the lowest performing cards, and the rest of the cards will follow that clock frequency. That way the cards in SLI are all nicely in Sync and are alternating your frames really synchronous. So all cards under load will be clocked / synced at the very same clock frequency. the screenshot I made above demonstrates that very clearly. So you take Afterburner, apply your overclock and all cards will follow and sync to the same clock frequency.
Overclocking made easy eh?, and yes that also means you can mix brands if you wanted to so. With the help of this feature and our tweaks, all three GeForce GTX 980 cards are now overclocked above 1400 MHz and run close to 8 GHz on the memory (effective data-rate). Pretty cool stuff huh ? So again let's boost some performance in 3-way SLI :)
For all overclocked games above we have used the very same image quality settings as shown before. Overall the generic rule of thumb here for a decent tweak and overclock is that performance can gain anywhere from 5 to 20% performance. The end result depends on a lot of variables though, including power limiters, temperature limiters, fill-rate and so on, the performance increment can differ per card, brand, heck... even cooling solution and your chassis airflow.
