The PSU you bought is probably <i>better</i>. The 400 watt model has a lower efficiency rating.
Whether <i>any</i> of the Antec PSU's are good enough for an power-hungry computer system is a debatable subject, IMHO. It may depend entirely on the individual unit. But I've RMA'ed more Antec PSU's this year than any other brand.
If that was my system, I'd have bought Sparkle, Leadman, or Enermax, 350 watts or better. But that's my preference. I don't see much point in using cheap PSU's in a performance system, and I also don't understand the rigorous arguments found on this forum in support of such. Trying to save money is admirable, but PSU's of low quality that deliver dirty power to the system components can cause tons of irritating problems, including downtime. And who likes that?
What you have purchased is likely to be sufficient, if there is nothing inherently wrong with the PSU. But I'd keep an eye on the voltages, anyway ... just in case.
Here's a link to the GeForce Faq page, which might give you some additional information about the minimum PSU specifications for this kind of video card.
<A HREF="http://www.geforcefaq.com/faq.html" target="_new">http://www.geforcefaq.com/faq.html</A>
The AGP port is particularly sensitive to voltage fluctuations, and regular games crashes can sometimes indicate an inadequate PSU.
Toejam31
<font color=red>My Rig:</font color=red> <A HREF="http://www.anandtech.com/mysystemrig.html?rigid=6847" target="_new">http://www.anandtech.com/mysystemrig.html?rigid=6847</A>
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