420 watt Thermaltake PSU or 400 watt Antec?

[Achilles17]

Im getting a comp from a friend with a 420 watt Thermaltake PSU in it, but i also have a 400 watt Antec PSU lying around, which one do you guys think i should use? I know both are decent, but is Antec better enough to make up for the 30 watt difference? the computer is a VERY heft system, so im worried 400 wouldnt be enough, but he ran it on the 420. here are the specs:

P4 3.2C
2 gigs of XMS PC4400 (i know, its overkill)
2x200gb hdd's with 8mb cache
dvd +/- rw
cd rw
audigy 2 zs
9800 xt
7 case fans
floppy

should i just buy a completly new PSU? keep in mind i plan on OCing as well...

[Mr.Radar]

The Antec you have is a SmartPower PSU which isn't the best. It's better than generic junk but the Thermaltake would probably be a little better. Also, have you considered the 430 watt Antec TruePower or the FSP350 Fortron/Sparkle models?