CPU: AMD Sempron 140
CASE: open (n/a)
HDD: 16 GB SSD
3x ATI 6970's (slight overclock)

Do you think I can reliably run 3 of these ATI's on a 1,000 Watt PSU?

Using Newegg's Power Supply Calculator, it says I would need 1168 Watts.  Hoping to get by with less, if possible.