I think you might have a poor HD7850 model there. Some of them are not that noisy at all.
My pre-overclocked GTX660 with a SB Xeon E3 1220(80W TDP),two full sized HDDs and a SSD was lucky to see 200W at the wall when running a very intensive game.
Even at 1680X1050 in some games like Crysis3 it can be pushed. The GTX750TI unless overclocked is slower than a GTX660,and considering the GPU looks to be non-upgradeable I would not touch the Alienware with a bargepole.
At least a PS4 will last a few years,but in two years a soldiered on GTX750TI is going to be quite outdated especially with DX12 being released.
It would have been better if they soldiered on the CPU and made the graphics card upgradeable,especially considering even Intel is saying this:
http://forums.hexus.net/hexus-news/3...ectx-12-a.html
Back to the drawing board Alienware. Not interested in a £400+ un-upgradeable paper weight.
Basically what they have done is taken a laptop and plonked it in a desktop case.
Laptops with Kepler based GTX850M and GTX860M cards(same GPU as the GTX750TI) can be had for around £550 to £650 which is not much more than the nearly £450 of the Alienware.
Now,if the Alienware has something meatier than a GK107 then it might make more sense. I really doubt it.