As mentioned above, I have an Antec 430 Earth Watts power supply.  Currently I have a E2140 OC'ed to 2.67 GHz, 2 GB DDR2, XFX 8600GT OC'ed slightly, 2 WD hard drives, and a DVD burner.  All attached to an Asus P5K-e WIFI.
 
I'm going to be adding another DVD drive, but I'm sure I can handle that.  My question is if I can upgrade to either the new E8400, or one of the new 45nm quads and a 9600GT without having to upgrade my power supply.
 
I looked at one of the online power calculators, and apparently, if I run the E8400 at stock, it will draw less power than the E2140 OC'ed at 2.67 (upgrade to 3.0 ghz and 6x the cache with less power draw?!?), does that sound right?  Also, can this Antec handle one of the new GPUs?  It's got 2 12V rails with 17A each, but I'm not really sure what that equates to.....
 
Thanks!!

The e8400's less power draw because its based on 45 nm tech as opposed to 65 - but im no good at power calculation, so i cant answer anything else

e8400 uses 1 amp more than the e2140 at stock.
Just about the same.
You need 20-21 amps on the 12v rails with your present system. With that Antec you have combined 30 amps on the 12v rails (360/12).
9600GT needs 26 amps on the 12v rails, so you are fine with the e8400 and 9600GT.