The Trinity series was not very overclocker-friendly. Even though, like the new Richland APUs, they included special K-indexed models with unlocked frequency multipliers, their Piledriver modules already worked at high frequencies, over 4 GHz. With the same manufacturing process and semiconductor design, the Richland APUs are clocked at even higher frequencies. Considering that Socket FM2 processors of the Trinity generation used to speed up to 4.5 GHz with air cooling, we might expect the same overclockability from the Richland generation.
Well, the actual results are somewhat better than expected. After increasing its voltage to 1.5 volts and enabling Load-Line Calibration, we made our A10-6800K stable at 4.7 GHz. It was cooled by an air cooler NZXT Havik 140.
The clock rate of 4.7 GHz, even though definitely better than the results of the previous-generation processors, doesn’t look impressive at all, though. It only sets the frequency of the A10-6800K higher by 300 MHz in the Turbo mode, so there are but minor performance benefits compared to the default frequency.
It is the high temperature of the 32nm APU die that prevents us from getting better results. To ensure stability at high clock rates, it is necessary to step the voltage up quite aggressively. The temperature grows as the consequence, with a threshold at 120°C. Upon reaching that threshold, the protection mechanism is triggered. So, efficient cooling is most important for successful overclocking of Richland-based APUs.
Our second unlocked processor, A8-6600K, turned out to be identical to its senior cousin in terms of overclocking potential. It was stable at 4.7 GHz with a voltage of 1.5 volts.
Thus, our A10 and A8 series APUs have the same overclocking potential.
Our A6-6400K processor, based on a single Piledriver module, could be overclocked somewhat better. Being simpler in design, it doesn’t get as hot as the quad-core A10 and A8. So, after setting its voltage at 1.525 volts, we made it stable at 4.9 GHz.
Generally speaking, the Richland series overclocks in the same way as other modern products from AMD. Every processor with Piledriver microarchitecture has about the same frequency potential. With air cooling, they cannot reach 5 GHz or higher. On the other hand, the 32nm manufacturing process is steadily being optimized, pushing the frequency bar higher. The Richland is a good example, differing from the previous generation with increased clock rates in the first place. Similar things can be observed with the Socket AM3+ platform for which AMD has recently rolled out a couple of FX-9000 series models.