GeForce 5950 - Bad Card or Not Enough Power ?

I got a PNY Geforce 5900 AGP card, the bios is flashed to a 5950, and
I have the abit IT7 mobo, and "HAD' a 350 watt power sup, but soon
found out it wouldn't suffice for the new card...as it would
constantly just make a glitch click noise and the screen would fill
with a solid pattern of orange or multicolored waves, and I would have
to turn off the cpu, as a hard reboot still had the distorted screen
upon restart. I checked on the PNY site and they said that this is
common if the p.s. isn't adeq. SO I got a Antec 450watt...that was
used and I think it might be iffy, as I had the card working for a
good 4 weeks, it never does this lockup in safe mode, and I have tried
over 15 drivers to see if that might help...but always when it will
even be sitting at the desktop, it will just make a click and the cpu
will freeze..
STuck as to what I need to try next

ANy comments or suggestions are much appreciated