You are around 400 watt power consumption.
For a 6850 a good quality 550 watt unit is recommended.
Antec, Corsair, SeaSonic are a few good brands too look for.
How much do you have to spend on the power supply?
I can spend around $90-100
I'm thinking of buying the Thermaltake ToughPower (W0103RE) (600W).
Is it a good PSU?
Thanks for your reply.