A nice Nvidia 6800 is consuming some 110 Watts. That's quite a load that your 380 has to carry. The PSU is not an item to stress or skimp on. In your case, some ATI 9700 or Nvidia 5700 may be some 40 Watts but still could tax your (unspecified) system.
You also didn't share what video card you are removing or the make/model PSU you have. Some are true to their ratings and others need you to discount a third off the total Watts to stay out of trouble.
Bob
im looking for a video card for gaming and i was wonderin if these would work with a 380 watt power supply...
http://www.newegg.com/Product/Product.asp?Item=N82E16814140048
http://www.newegg.com/Product/Product.asp?Item=N82E16814150102
http://www.newegg.com/Product/Product.asp?Item=N82E16814150067
i hope u guys can help me out on this one

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