Power supply confusion

[Prosthetic_mind]

I'm currently building a computer (Fatal1ty AN8 SLi, Athlon 64 X2 4400+, 2 gigs of ram, etc.) and I'm completely unsure as to how much power I need and what power supply to get. I know my hardware pretty decently, but I have no idea as to what sort of power supply to get. I have been told to look into a 600W, but I have no idea which one to put into. any help would be appreciated.

[saphalline]

Judging from those initial specs, I'd say your starting point is 450W. Whether or not you need more depends on your vid card(s) and how many drives you will have. I don't think it's unreasonable to suggest 600W (especially if you're planning on having a high-end vid card and more than 4 drives) but that can get really pricey! :eek: Of course, a PSU will only use up as much power as your computer needs at any given time, so a 600W PSU will not increase your electric bill vs a 450W PSU.

Another thing to consider is the quality of the PSU. This is important!! A high quality PSU will deliver more and better power than a cheap one, and will probably last you years. Stick to known good manufacturers (such as Antec, Thermaltake, PC Power & Cooling, Enermax, etc) and you will never have to worry about the quality.

Finally, you'll need to look into ATX 3.0 (aka ATX 12V 2.0) power supplies since they have the necessary 24-pin power connector that you will need for that mobo. It will also have native SATA power connectors, dual +12V rails, and (if required by the mobo) the extra 6-pin PCIe power connector. It's always nice to have a PSU that works out-of-the-box. ;)

Cost for a PSU with all of these requirements = $70-120 (average) depending on wattage.

[Prosthetic_mind]

Thanks a lot, one of the things that I have the hardest problem finding is the amount of power required for each component, at least the major ones (video card & mobo) am I blind or are they not there? I plan on starting with a really high end video card, looking at the AOpen PCX6800Ultra-DVD512 Geforce 6800Ultra (http://www.newegg.com/Product/Product.asp?item=N82E16814135174) and then later after building up more cash and letting the prices go down grabbing another and linking them.

[Prosthetic_mind]

I finally decided on the power supply I'm grabbing (with quick help from an uncle who found one on sale and is giving it to me), an Ultra X-connect 500W power supply (with lighted cords, something like this-http://www.ultraproducts.com/product_details.php?cPath=37&pPath=157&productID=160). Since it is rated for continuous power, that would mean that the actual peak power is above 500W, right? Which would mean that it would probably suit my needs, with a little to spare?

[saphalline]

Oooh, I don't like that PSU. The modular cable idea is a great one, but that power supply in general is not high quality. On top of that, it doesn't have dual +12V rails and it doesn't have the new 24-pin main ATX power connector. In short, it looks pretty but it won't be up to the job of powering a major system.

I do agree, however, that your target wattage should be 500. Let me recommend this Antec (http://www.newegg.com/Product/Product.asp?Item=N82E16817103932). Yes it's a lot of money (relatively speaking) but I doubt you really want to fry the first vid card before you can afford a second one, right? ;)

[pentachris]

Maximum PC reviewed a X-connect power supply several months ago. I don't think I still have the magazine, but they weren't impressed.

Here's (http://www.tomshardware.com/howto/20050228/power_supply-11.html) the THG review.

Performance

While the unit delivers the required power, the 3.3 V rail drops to 2.95 V at max load - far too much of a drop compared with the specified limit of 3.14 V. Even at half load, the 3.17 V readout of the 3.3V rail nearly approaches the tolerance limit. All other voltages fell within tolerance limits in our test.

The 74% efficiency we measured under half load is respectable, and 70% efficiency at maximum load is also acceptable, but 61% efficiency at low load is decidedly too low. In that case too much cold, hard cash is vaporized as thermal loss - a fault the manufacturer absolutely has to remedy.

Personally, I like Antec as well.

[Prosthetic_mind]

Thanks a lot. You saved me from making a mistake that could have been quite costly. The video card is good too, right?