Power Consumption And Battery Life
With different CPUs and hard drives in the old and new systems, we can only say that the Radeon HD 6990M appears to draw more power than the Radeon HD 6970M at full load. The evidence is a little more convincing when we say Nvidia's GeForce GTX 580M draws more full-load power than its GTX 485M predecessor.
It's easier to compare systems that employ the same CPU and drives.
The Radeon HD 6990M draws around 14% less power than the GeForce 580M in 3D mode, while the GeForce GTX 580M has lower power consumption in 2D mode. SLI and CrossFire change the picture slightly at idle, though Nvidia's GeForce combination is still super-thirsty at full load.
Battery Eater Pro applies a minimal 3D load that appears minor enough to keep Nvidia's cards from running at full blast, adding several minutes to overall battery life. While desktop replacement notebooks are not intended to run off-the-wall for extended periods, it’s nice to know that you’ll be able to check your email while taking a coffee break.