I will be getting an Alienware Area-51 7500 with 1 768MB NVIDIA GeForce 8800 GTX and I will get another 8800 GTX next year... alienware customise page say I will need the 1000w PSU at £65 extra to power them both in sli. So my question is do I really need the 1000w PSU or will the 700w PSU do? £65 less on the bill will be nice plus save on my eletric bill at home.
 
Here are the specifications of the 700w PSU...
 
 
Type ATX 12V 2.0 (quad +12V rails)
 
Continuous Power 700 Watts  
 
Maximum Power 760 Watts  
 
Output +3.3V@33A, +5V@24A, +12V1@13A/18A, +12V2@18A, +12V3@16, +12V4@8, -12V@0.5A, +5VSB@2A  
 

wow, that looks pretty sh*t for a 700W psu...i know a pc p & c silencer or a thermaltake toughpower 750w would be able to drive it but i'm thinking that is quite weak for a 700W, what model is it and who is it from, or is it  "in house"?

 
 
Such a contrast to what you say :S
 
The Alienware approved 700 watt power supply unit provides clean, stable power to critical system components to ensure reliable, rock-solid system operation - day in and day out. One of the most common failures suffered by PC systems is a faulty power supply, and is often due to cost-cutting measures taken by the power supply or PC manufacturer in order to deliver a more affordable system, albeit at the expense of quality. The Alienware approved 700 watt power supply is just one of the many high-quality aspects of Alienware systems with a focus on keeping you and your system up and running.
 
   

 
Assuming the efficiency is the same on both power supplies, your electic bill won't change one bit.  A PSU only delivers the power your system requires.
 
Read #1 here:
 
http://www.pcpower.com/technology/myths/
 
-TyShoe

 
Hey, if you see a YAHA 300W ATX power supply in real life it will be a piece of junk, but if you read about it from their site you'll think the sun shines out of its...

You're getting a Dell dude!   To Quote the comercial.
I thought that Alienware quality might go down since Dell bought them out.
 
http://news.com.com/Dell+to+acquir [...] 52842.html