Quote: "Minimum power supply for 8800GT should be 400W. Recommended 500W and up. I just got my 8800GT Overclock edition yesterday "
How many watts is your power supply?
I took out the 400w that came with my system that had a 8500gt.
I replaced it with a 600w when I bought and installed my 8800gt.
I would not suggest running a minimum, because different systems have different components sharing that power supply.
So, a quad core is going to need more power than a dual core, and multiple hard drives require more power than a single one, etc.
Another reason not to run the minimum power supply is that you can't upgrade anything else later without possible power problems.
Quote: "it says there is no graphics card in my computer, any ideas why from that explination?"
If it isn't seated properly, then it won't detect it.
You may also want to try to re-seat it, because sometimes the pins don't line up and make contact right when you push it in.