Overclock your GPU 1 MORE PROGRAMS

Similar to CPU benchmarking, you need to download some software to get this baby started. Firstly, download GPU-Z — this program tells you exactly what GPU you have, and all of its stats, and also monitors maximum boost clock, memory frequency and temperatures. You also need a quick synthetic benchmark, such as Furmark, to synthesise load, a more in-depth 3D benchmark, such as Fire Strike [Image A], an in-game benchmark (that’s Far Cry Primal for us), and a program to overclock with. For Nvidia cards, we suggest using MSI Afterburner; for AMD, either use the integrated Wattman overclocking utility in Crimson, or Sapphire’s TriXX software, depending on what you have available for your card. In this instance, we’re overclocking the Nvidia GTX 1080, but the principles apply across both brands.

2 MORE PRELIMINARY TESTS

We want to benchmark the card at stock, and note down how the card performs in a spreadsheet. So open GPU-Z, click the ‘Sensors’ tab, click the drop-down arrow on ‘GPU Core Clock’ and select ‘Show highest reading’. Do the same for ‘GPU Memory Clock’. Now open Fire Strike and run the standard benchmark at least twice. Note what GPU-Z states for the highest Core and Memory Clock frequencies [Image B]. This is how far GPU boost is pushing your core at stock. Note the average Fire Strike score, then run your in-game benchmark and take note of that as well. You can also write down the temperatures here (check GPU-Z), but you’ll run into silicon limits long before thermal ones.

3 RAMP IT UP

Open up MSI Afterburner and increase ‘Power Target’ to the maximum. Don’t worry about it increasing ‘GPU Temp Target’, as it’s still well within operating parameters. Next, start increasing ‘GPU Clock Offset’. To begin, increase it by 50MHz, and hit ‘Apply’. Open up Furmark and set it to a resolution appropriate to your card (we’re looking to emulate 100% load without stuttering). For our GTX 1080, that’s 2,560 x 1,440 at an AA setting of x4. Run ‘GPU Stress Test’ and see if Furmark or the screen locks up. If it’s still stable after three minutes, increase the clock offset by another 50MHz. Keep doing this, making notes, ‘til you lock up.

4 CIRCUMVENT VOLTAGE ISSUES

Now you need to overvolt the card to pump the core clock higher. In MSI Afterburner, go to Settings, check ‘Unlock voltage control’ in the first tab, then change the drop-down to your type of card. Go back to the main interface, add 10mV/10% extra on the overvolt section, and try your overclock again. If this doesn’t work, keep adding voltage until you get to around +40% — anything higher and you’ll probably see stability issues. After that, it’s a case of finding the sweet spot for the core clock. Increase or decrease by 10MHz until you find the GPU’s limits.

5 CHECK FOR GRAPHICAL ANOMALIES

Now we have a stable overclock with Furmark, see how it holds up in a more intensive benchmark. Open Fire Strike and run a single instance. You need to watch this. In particular, you’re looking for anything that shouldn’t be there: graphical anomalies, such as flickers, green or purple particles, anything that isn’t in the original. To save time, go to the custom settings and run Scene 2 or Scene 4, as they’re the most graphically intense.

6 ALL ABOUT THAT MEMORY

To complete your overclock, improve the VRAM. To do this, go back into MSI Afterburner [Image C] and slowly increase the memory clock, again by 50MHz at a time. Generally, VRAM tends to be predictable about how high you can clock it: GDDR5 and 5X averages an increase of 400– 500MHz, while HBM usually manages about 50MHz before it starts to fall over. Once this is done, and Furmark is still responsive, go back into Fire Strike and look for anomalies again. Fortunately, memory overclocks tend to be more aggressive in how those anomalies appear. If you’re having trouble, drop down the memory clock by 10MHz each time, until you manage to get it stable. If you’re still having trouble, and you’ve dropped down by 200MHz or more, try going back up, but reduce the overclock on the core by 10MHz at a time instead.

7 TRIAL AND ERROR

GPU overclocking is always trial and error. Because there are two different components to overclock, it can take time, but once you’ve got a stable profile dialed in, you’re good to go. Save the profile in MSI Afterburner, note it down in your spreadsheet and crack open GPU-Z once more. Set the sensors we changed earlier back to the highest reading. Run Fire Strike two or three times, plus your in-game benchmark and you should see a marked improvement over your stock settings.