hi overclock is own risk ! I think 450 w antec basic enough for it but more power will be better.
I'm not sure about ddr3. try go rather for 8x muliplier x 400 FSB. Neat 3,2Ghz and 1:1 with your RAM. you can always try 8.5x400. I also started Overclock with a standard cooler, experienced on 3,6Ghz, standard Vcore ( do not auto ) Test use prime95 8hours or use IBT 20time maximum ram. Alway's keep temperature below 70C, you will be fine.
Next stop should be a guide for your particular motherboard. Google is your friend.
Go through the guides. Then take your core voltage off Auto and set your memory voltage to factory recommended values. Change the System Memory Multiplier (or whatever your BIOS calls it) from AUTO to 2.00, 2.00B, or 2.00D - whichever you need to set the Memory Frequency to twice the FSB. Then when you increase the FSB, the memory clock will rise in in proportion with it. At an FSB of 333 MHz, your memory clock should be at 667 MHz. At 400 MHz FSB, your memory clock should be at 800 MHz.
If you find your DDR2-667 memory is limiting you, try increasing the RAM voltage to 2.2 volts. If that doesn't help, try relaxing the memory timing from 4-4-4-12 to 5's-15 or from 5's-15 to 6's-18. One nice thing about Core2 systems is that memory performance (or lack of) doesn't have a large effect on system performance.
Run your internal CPU multiplier at X9 (max).
Keep your core voltage under1.45 volts and your load temps under 70 C.
Don't worry about your power supply. Overclocking your CPU will add no more than about 15 watts to your power consumption.
Download CPU-Z to check your FSB:RAM ratio. It should be a 1:1 ratio.