The GTX 970 Phantom works at a base clock of 1152MHz, while the reference GPU base clock is 1050MHz. Nvidia's GPU Boost 2.0 takes the average GPU clock to 1178MHz for the reference GPU and to 1304MHz for the Phantom card.

The overclocking potential is not as good as on some custom GTX 970 cards, but considering that this is a factor overclocked card, we can be happy with +90MHz for the GPU and +150MHz for the memory, using standard voltage, at maximum fan speed.

One contributing factor may be the Phantom cooler with two fans, as well the limited Power Target, which limits the GPU clock in many situations. There is not a lot of tinkering that can be done with the GTX 970 Power Targe, as it’s set to 106% and we could not go over it. The card hits the target even without any additional overclocking. The GPU temperature reaches the throttling point of 79-80 degrees Celsius even when the card works at factory oveclock. This temperature poses no threat for the GPU, but it’s the threshold at which the dynamic overclocking algorithm starts to kick in. The Boost 2.0 algorithm kicks in from time to time and does not allow the card to run at the maximum frequency all the time.

We scored better results without further overlooking, just by increasing speed of the two fans.