I have Platinum MS 400ATX P4 400W psu , my friend said i have only about 80-90W for a graphic card . I really really really want to get AMD Radeon HD 6850 Gigabyte edition , also i have an option to get AMD Radeon HD 7770 Sapphire GHz Edition, 7770 is a little cheaper but from what i've seen , the 6850 is way better , could my PSU handle it ? And im getting that 250W Thermaltake graphic card PSU for a few days , what is ur opinion?