Advice on power supply for Radeon x1950 Pro

I was recently given a video card by a friend of mine so I installed it in my old Dell 8250, here is the card:

http://www.visiontek.com/products/ [...] o_AGP.html

It says it needs at least a 450 watt PSU with 30 amps on the 12 volt rail, however the PSU I am running is only 410 watts with 23 amps on the 12 volt rail. The card seems to run fine, I was just wondering if I might encounter some problems later due to not meeting the power requirements, here is my PSU:

http://www.pcpower.com/power-suppl [...] ell-2.html

Ive heard that PC Power and Cooling makes good PSUs and are often rated at less than what they can actually handle. Is this PSU good enough or should I worry? This is pretty much the best PSU I can get for the system I have.