Use this page for your referencing of the latest (and part of the previous generation) graphic card and its power consumption.

Besides that, you’ll also be recommended the PSU wattage rating that you should acquire in order to use the card.

If you look at the columns, you’ll see 3 columns on the right side titled “Low”, “Medium” and “High”. These basically divides the common computer setup to 3, with LOW spec being the average low end dual-core, HIGH spec for those machines that of monstrous power consumption (eg Intel Core i7, multiple hard disks and high RPM fan and so on) and the MEDIUM spec for everything else in between.

While most machines barely consume more than 150w at any one time, we’ll be assuming that all the setup are at full power usage, with LOW spec at 150w, Medium spec at 200w and High spec at 250w. (ratings not inclusive of the graphic card).

The recommended PSU wattage is not the figure of the graphic card + spec combined, that would be silly. The combined wattage is 70% of the recommended PSU wattage as PSUs generally are most efficient at around that %. This also mean there’s plenty of headroom for add-ons (it’s fine to run on higher % of the PSU capacity, I’d say try to stick within 85%) and also to cater for PSU deterioration. It’s unwise to run at near 100% PSU capacity, furthermore not all PSU could provide 100% of what they claimed.

Lastly, do take note of other factors such as the Amp (A) ratings supplied by the PSU’s rails. More details here.