im building a computer for someone and i got a 350 watt power supply and 450 wattage
im trying to power http://www.newegg.com/Product/Product.aspx?Item=N82E16814187034 what is the maximum wattage i cant figure it out
does anyone know?

Just look at the manufacturer specifications on the AMD's or Nvidia's website, they always have them.

http://www.nvidia.com/object/product_geforce_9500gt_us.html

(It says 50 watts)

For figuring out the total wattage you need I make the following assumptions:
RAM = 50
CD Burner =25
HDD =25
4x120mm fans = 20 (rough estimate)
Motherboard = 50

Then look up the GPU and CPU draw.

Alternatively I've found Asus's PSU calculator to be generally accurate, though it tends to round up a bit:
http://support.asus.com/powersupply.aspx

thanks so much perfect perfect 450 should power everything

That's a pretty old card (and a small budget card, by the looks of it), you should be fine.

my main pc has a 1k this is just for someone who is obsessed with wow and fallout, i hope this card runs those