Can my power supply support my video card?

I was curious, I have a Nvidia Geforce 6200 graphics card. I was looking into getting a new video card, that requires at least a 400 watt power supply. My current power supply is only 250 watts. I checked out my current video card's specs, and saw that it requires 300 watts. Will that decrease my video cards performance at all?|||I suggest getting a new power supply as high as 500 watts, not hard to install.|||Your computer likely won't run well at all. If you PSU doesn't have enough to power just 1 component then it's definitely not going to be able to power the rest of the computer at the same time.