Times when serious gaming systems could do just fine with 200-250 W power supplies are long gone. Today graphics accelerators have become one of the most power-hungry computer components having left even the most powerful CPUs far behind, even though they still hold the proud second position in this rating. From time to time things roll a little backwards, as ATI/AMD and Nvidia switch to new manufacturing technologies, but the overall tendency is undeniable: the graphics cards power consumption keeps increasing as they become more and more powerful. This is the price you have to pay for 3D technological progress. Of course, choosing the right power supply unit is of utmost importance especially to the dedicated gaming fans, who enjoy their favorite titles with maximum image quality settings, highest level of detail and enabled antialiasing. In this case the most powerful graphics accelerators can consume up to 200 W easy, or maybe even more than that, however, there are barely any data about these power consumption levels at this time. Most reviewers usually measure the overall power consumption of the system as a whole, but even these results are still not fault-free, as we have told you in our article called PC Power Consumption: How Many Watts Do We Need?.
More complex methodology, which, however, guarantees more precise and complete results, implies measuring the currents going through different power lines of the graphics accelerator. We have been using one of the variations of this approach until recently, namely, we installed measuring shunts into all graphics card power circuits including PCI Express power lines. However, this approach was not ideal: first, it required us to modify the mainboard pretty seriously; second, it didn’t allow any automatization of the actual measuring process; and third, it used Futuremark 3DMark06 and PCMark05 to load the GPU, which have already become completely obsolete. Although this method allowed us to gather a significant data base of graphics cards electrical characteristics, it no longer poses any significant interest in 2010 for the reasons mentioned above. Namely, outdated software is no longer capable to squeeze all juices out of the contemporary graphics accelerators, which means that the power consumption readings obtained using our old approach will be seriously underestimated. Moreover, graphics processor developers have been actively migrating to finer 40 nm process and have released quite a few new generations of energy-efficient GPUs, which are also worth checking out from the power consumption standpoint.
As a result, time definitely called for a new article that would discuss the power consumption levels of contemporary graphics processors in different modes and that would use more advanced up-to-date testing approach. Since we have already developed this methodology and have been using it for quite some time, all we had to do was to apply it to all graphics accelerators available in our test lab at this time and sum up the obtained results in easy to read format for our readers, which is exactly what we did today. Our article will tell you about the energy-efficiency of the latest and existing graphics accelerators and about the electrical peculiarities of the popular GPUs during overclocking. Moreover, we hope that the obtained results will help you better understand what power supplies your gaming platform may need depending on its configuration.