shovenose

Distinguished
would it be better than my current gfx card?
will it kill my psu?

specs:
Xtreme PSU 400w dual-fan lp-6100d +12v 25a
athlon 64 x2 s939 2ghz 3800+ dual core
1gb (2 x 512) ddr
wd sata hdd
seagate ide hdd
dvdrom ide

TAHNKS IN ADvANCE!!!
 
Yes it should be fine the card requires at least a 20 Amp 12 volt rail so you should be OK but you will need an 6 pin PCI E connector or you might need an adapter if you dont have one.

Edit: I just looked up your PSU it doesn't have a 6 pin PCIE connector so you will need to get an adapter.