How much wattage do I need in a PSU for my system?

[Zinthar]

I'm looking for a budget/semi-budget PSU for my new build, which will include an E6400 OC'd perhaps up to 3.2 Ghz (looking into using a Scythe Ninja on the CPU & maybe a different NB heatsink on my Gigabyte P965-DS3). I'll be running one optical drive and one SATA HDD (but may add another of each later), 2GB RAM, 2-4 fans, and a Radeon X1900 XT. I plan on OC'ing the X1900 to XTX clockspeeds (I'm using the DS3 mobo, so I'll never be able to do SLI/Crossfire, but I likely will upgrade to a DX10 video card in 2008).

How much power do I need to make this happen?

My current top choice is a Coolmax 550W PSU that features a 140mm fan:
http://www.newegg.com/Product/Product.asp?Item=N82E16817159033 (would cost me $68 shipped considering I would get a $20 combo discount if I buy it with the Patriot PC2 5300 DDR2 4-4-4-12 RAM I'm looking at buying)

I'm also considering a Fortron 450W at $61 shipped, and an Enermax Whisper 460W at $78 shipped.

I'm trying to do this on a budget. Any recommendations?

 

[acegazda]

I think the question is not "how much wattage" but how much ampage. Many of the better psus have great amp ratings on the 12v rails, which by the sound of it is important to you. That coolmax is not even sli certified. It's a 550w unit. It should be if it was a good psu. The majority of the power is pocused on the 5v rail, with a ridiculous 50amps. The enermax whisper is a great choice, however I might venture to say that you could do well with a solid 400w psu. Perhaps an enhance 5140gh, a fortron fsp400-60n or an enermax liberty. All are <$70. Happy building!

 

[brave71heart]

If u r going with Enermax i found this 485W Noisetaker 15 bucks instant savings and free shipping @ Newegg for 74.99.
http://www.newegg.com/Product/Product.asp?Item=N82E16817103457

 

[stu1811]

1.21 JiggaWatts should do the trick

 

[GalvanizedYankee]

I would avoid the Coolmax. My humble offering.

Enhance ENP-5150GH (500W) or ENP-5140GH (400W). They sell at http://www.ewiz.com/
for $69 or $58, both are http://www.80plus.org/ certed, specs at http://www.enhanceusa.com/

If eWIZ bothers you, both will Froogle for about $5 more.


...Galvanized

 

[Zinthar]

Thanks for the advice...I'm torn between the Enermax 485W and the Enahance 500W. Both are approx. $75 shipped. The enermax has excellent reviews on Newegg, but the Enhance seems to be a relatively unknown high quality PSU with the 80% efficiency guarantee. Both claim to be quiet, so I'm leaning towards the Enhance.

 

[n7]

Enhance is superb, just ask teh gurus here.

IIRC, they actually make the PSU you buy, unlike the majority of manufacturers, who just rebadge.