Overclocking

The overclocking results listed in this section were achieved with the default fan and voltage settings as defined in the VGA BIOS. Please note that every single sample overclocks differently, which is why our results here can only serve as a guideline for what you can expect from your card.



Since NVIDIA sent us three cards for tri-SLI testing, we tested each one individually for maximum overclocking potential. This larger sample size provides a better view on what clock speeds can be expected.

The best card reached 1005 MHz GPU clock (20% overclocking) and 1755 MHz memory (17% overclock).

Overclocking potential is quite good. 1 GHz is probably possible with most cards. Memory clocks reached the levels we would expect given the high-quality GDDR5 memory chips used.

Important: Each GPU (including each GPU of the same make and model)
will overclock slightly differently based on random production variances.
This table just serves to provide a list of typical overclocks for similar cards,
determined during TPU review.

Overclocked Performance

Using these clock frequencies, we ran a quick test of Battlefield 3 to evaluate the gains from overclocking.


Actual 3D performance gained from overclocking is 21.0%.

Voltage Tuning

It has been a long known fact that overclocking headroom increases as soon as you increase the operating voltage. Software voltage control on VGA cards has, until recently, been the exception and most users were not willing to risk their warranty by performing a soldering voltmod. Almost all current graphics cards have voltage control in order to lower power consumption by throttling voltage during idle and slight load.

In this section, we will increase the GPU operating voltage step by step before recording the maximum possible clock speed. Voltage is listed as the value that the voltage regulator reports through software, not actual measured voltage. The card was installed into a case with fan settings at default. Memory will not be overclocked. We will, with a card that has thermal throttling, reduce the operating frequency to keep performance as high as possible for a given voltage. Please note that the fan profile will have an effect on observed temperatures: if the card gets hotter, the fan will ramp up to reduce temperatures or keep them from rising too fast.

The following graph shows the overclocking potential we saw on our sample. GPU clock is represented by the blue line, which uses the vertical clock scale on the left. The scale starts at the default clock to give a feel for the card's overclocking potential over its base clock. Temperature is plotted in red using the °C scale on the right side of the graph. An additional graph shows full system power draw in orange, measured at the wall socket while running at the given voltage, clock, and temperature.



Increasing GPU voltage did not yield much of an improvement. This seems to be largely caused by the limited voltage range. The highest setting is 1.2 V.

We also tried increasing the power limit to the maximum of 106% and raised the thermal target to 94°C, hoping it would allow for higher clocking potential.



As you can see, we gained a bit more OC potential that way, but voltage scaling is not anywhere near what we've seen on some AMD HD 7970 GHz cards.