I am putting a new system together with all of the latest gizmo's. At least as far as I can afford, and it looks like I will need to pick a new Power Supply. I'll be running Vista Home Basic x64 on a new MSI Motherboard with an AMD Phenom Quad Core 2.3 GHz, NVidia chipset, 2 600Gb SATA hard drives, 8 GB's of DDR2 800 MHz RAM, a 500 MB NVidia PCI-Express card, a Creative Audigy SE PCI sound card and an IDE DVD ROM and Burner. I was hoping I could stick with my Coolmax 550 watter, but the Coolmax tech tells me otherwise, even though on the Thermaltake Power Supply Calculator it says I need only 525 watts. I'm not sure if I entered in all of the valiues correctly on that though. So it looks like it's time to shop for a new Power Supply then, and right now I'm leaning on two of them, a very quiet Nexus 600 watter that I chose because I'm going with their case fans: http://www.endpcnoise.com/cgi-bin/e... And an Antec 650 watter: http://www.ewiz.com/detail.php?p=PS... The Antec's a little cheaper because it's not as fancy, but reviews say it's very quiet. Plus I've always had good success with them. So that's where I'm at right now. Down to those two, though open to other suggestions. Price is somewhat of a factor. I've spent quite a bit already on the whole system and I want to start slowing down the purchasing craziness, though I still do not want to stop short on as key an item as a power supply is. One more thing. I was browsing New Egg for power supply's and I ran into this post from someone who appears to be looking at Power Supply's from an entirely diffrent angle than I am. I mean I'm tech savvy to a point, but I also know my limits. I was just wondering, first of all, if anybody can translate this to understandable English, and second, how right-on is this person? Here's his post on power supply's: "Don't just check total power output, find out what you need in the way of current on each power rail. If you need 20 A on your +12V rails and the supply only has 15A, it doesn't matter how many watts the supply puts out: don't buy it. Make certain that you have ENOUGH rails, too: sometimes, you need more than just two +12V rails for your setup." Jan LaFata

Multirail PSUs are falling out of favor. The problem is just what that poster pointed out. You can't take Amps from one rail and apply to another. If you have a power hungry graphics card you need enough Amps for it. Theorically the multirail units are good. The caveat is IF there is enough Amps on each rail to supply the hardware it will feed. Two high end cards in SLI or Crossfire will each take a rail. Another rail will feed the CPU. A fourth rail would supply the +12V to the remaining hardware that uses +12V. One example is in the link below. http://www.newegg.com/Product/Produ... This unit has 4 - 18A rails. That is enough for almost all current Graphics cards. The most power hungry card draws about 19A. Problem is they are fudging the numbers. The +12V rails alone would add up to 720Watts. The next link is for a 650Watt single rail unit with 52A on the 1 +12V rail. The +12V rail would require 520Watts, so this unit specs are probably more accurate. In case you are wondering how to calculate those numbers: Volts X Amps + Watts. So 12V X 52A + 520 Watts. That doesn't account for the 5V & 3.3V rails. http://www.newegg.com/Product/Produ... This should get you started. Below is a link to show power requirements for most graphics cards. They are the single biggest power user. The CPU is next. http://mark.zoomcities.com/images/g...

650W, 52A on a single +12v rail, over 80% efficient, $70 after rebate: http://www.newegg.com/Product/Produ...