Sapphire’s Radeon R9 390 Nitro comes overclocked from the factory, but of course we want to try pushing it further. No overclock is guaranteed though, and your results with the same hardware may differ from what we're seeing.
We used MSI's Afterburner software to overclock Sapphire’s Radeon R9 390 Nitro. The utility is compatible with most modern graphics cards, and many overclocking applications are simply derivatives of Afterburner.
Using the stock clock rate of 1010MHz, I ran 3DMark Firestrike to establish a baseline and recorded a score of 12,085. I then increased the GPU clock by 10MHz and re-ran the test. After each successful pass, the score was compared to ensure it kept climbing. This process was repeated until the first artifacts were observed, which happened at 1110MHz. A quick test at 1105 resulted in instability. Even a voltage bump of +6mV didn’t help mitigate the artifacts.
At that point, I settled on 1100MHz and moved on to the memory. Going with 25MHz increments from 1500MHz, the display started showing artifacts at 1550MHz. Due to my issues increasing the GPU clock, I backed it down to 1090MHz and tried tuning the memory again. This worked well; the memory subsequently scaled up to 1700MHz before presenting artifacts.
The high memory speed proved to be unstable, though. The 3DMark scores started to drop slightly after passing 1625MHz, and real-world games ran into issues at higher frequencies.
Ultimately, with a GPU clock of 1090MHz and a memory clock of 1625MHz (6500 MT/s), both settings were up nearly 8%. The extra processing power helped bring the 3DMark score to 12,901, which is over 800 points higher than the baseline. The overclock managed a moderate increase in performance in all games tested as well.