Like the Radeon R9 290X, the Radeon R9 290 has a rather inefficient cooler, so we had to fix its fan speed at 60% or 3380 RPM for our overclocking experiments. We didn't increase the card's core voltage. Still, we were quite successful, increasing the GPU and memory frequencies by 168 MHz (+17.7%) and 960 MHz (+19.2%), respectively.
The resulting clock rates were 1115/5960 MHz in 3D mode.
The GPU clock rate is just a little lower compared to the overclocked Radeon R9 290X (1130 MHz) but the memory frequency is 200 MHz higher. We guess that's a good enough result for a reference card.
At 60% fan speed the overclocked card had a peak GPU temperature of 87°C. The noise was high but the GPU frequency didn’t drop down:
We were overall pleased with the overclocking potential of the Radeon R9 290, especially as the overclocked card delivered high performance.