Antec HE550 - EVGA 8800GTS 320mb...

Hello all I am new here my name is Dylan. I am upgrading from my 7600GT-KO to the EVGA 8800GTS 320MB. I would like to know if you think my Antec HE550 PSU will be enough for that plus the rest of my system:

-AMD Athlon 64-FX 55 2.6GHZ
-MSI K8N NEO4 Platinum Motherboard
-4x512 DDR-SDRAM
-about 8 case fans
-A DVD-RW and possible a CD-RW
-Linksys Wireless Card
-2 SATA Hard Drives
-Hopefully!! EVGA 8800GTS 320MB

I would greatly appreciate any respsones or feedback. I have looked through several posts but I would like to be more specific to my system, which is why I posted this. Thank you again in advance. I have used the Extreme PSU calculator but I was confused because when I put the Video card it self in the equation it said on like 138 Watts, when the box says about 400 watts minimum.