It’s a fact that Nvidia have produced the overall better GPU with the GeForce GTX 680M. Its waste heat and energy consumption are both lower compared to the Radeon HD 7970M, leading to quieter system noise and longer battery life.

The manufacturer with the green logo continues to take the lead in supported features. In particular, PhysX and 3D Vision currently do not have any serious competition. Furthermore, AMD’s graphics switching technology is almost abysmal. Poor detection rate, few configuration options, and noticeable performance losses are just a few of the annoying problems. Nvidia’s Optimus definitely deserves praise for its much friendlier interface and better functionality.

On the bright side, the Radeon HD 7970M is not too far behind the 680M in gaming performance. In fact, both are about on par in games and the GTX 680M is even significantly slower in professional applications. However, the biggest advantage of the HD 7970M is its more reasonable price. Hardly any other high-end notebook GPU model can achieve better FPS-per-dollar ratio than this Tahiti core.

If AMD can improve upon the still-young Enduro technology, then we would recommend the 7970M without hesitation. But for now, the 680M offers the most balanced, reliable, and most versatile performance of the two.

Being that the 7970m and 680m are about equal performance wise with the 680m having better switchable graphics and power consumption, I can't see how they could recommend the 680m when it costs $380 more. Maybe $100.

[Nvidia] continues to take the lead in supported features. In particular, PhysX and 3D Vision currently do not have any serious competition. Furthermore, AMD’s graphics switching technology is almost abysmal. Poor detection rate, few configuration options, and noticeable performance losses are just a few of the annoying problems. Nvidia’s Optimus definitely deserves praise for its much friendlier interface and better functionality.

i can see poor battery life and annoying glitches being worth $400 in a high-end notebook PC without those issues
-- you think it is worth it to be annoyed for any price?

For example, i could never recommend the HD 6990 to anyone that is not deaf; it doesn't matter if it is significantly faster than the GTX 590 (which it is not)

So you think nvidia can justify pricing it's gtx 680m $400 more than the 7970m because it has better switchable graphics and battery life? Battery life is meaningless when we're talking about a behemoth laptop that won't get over two hours on a battery regardless of which gpu it has and needs to be plugged in to use the gpu at its full potential anyway.

No one with any sense would pay almost $400 more for the 680m to gain a whopping 44 min of battery life and draw a whole 16 watts less under full load.

For the GPU, Alienware now offers the GTX 660M (an 835MHz GK107), the GTX 675M (a rebadged GTX 580M), or AMD’s new tour de force, the HD 7970M. Interestingly, the HD 7970M is actually priced cheaper than the GTX 675M, which based on initial performance reports is bassackwards—not that we haven’t seen similar pricing oddities in the past, as NVIDIA’s top-tier GPUs almost always cost more than AMD’s.