Your opinions on the 500w Ultra Xfinity Power Supplies?

Looking to power a E6600 conroe w/ a 7900GT, couple of harddrives, 2 gig, and a DVD rom. Will the power supply suffice? The system will be mildly overclocked w/ 2-3 120mm fans.

I would go for a trusted namebrand like:

Antec
Enermax
Fortron
OCZ
Seasonic
Silverstone

and...

XClio - Relatively unknown and relatively inexpensive compared to the list above. But their PSUs have received good hardware reviews (not to be confused with user reviews).

500w is an overkill for your proposed system. Even a 400w PSU has enough power for your system with some to spare.

Yep, the Antec SmartPower is a good PSU so it's a keeper.

Just in case you are curious as to why 500w is overkill:

Component.............................Power draw on 12v rail
7900GT (Overclocked)................................56w
2 300GB hard drives (25w x2).....................50w
DVD Drive...................................................18w
Typical Motherboard....................................20w
Sound card.................................................10w
2 Sticks of RAM.............................................0w (draws power from the 3.3v rail)
Typical 120mm Fan (5w x3).........................15w

Conroe E6600 (stock)..................................64w* (see note below) => Updated

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Total Estimated Power Consumption..............233w => Updated


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The typical 500w PSU provides 32amps on the 12v rails that equals 384w (32amps x 12v).

The typical 400w PSU provides 25amps on the 12v rails that equals 300w (25amps x 12v).

As you can see from above, most components draws power from the 12v rails. That's why the 12v rail is so important. Also, the total power of a PSU doesn't really tell you much. It's more important to know how many amps are running on the 12v rails because:

Amps x Volts = Watts

* This is an educated guess based on the following:

1. A non overclocked X2 4800+ consumes 96w of power.
2. Based on following total system power consumption chart below:
a. assuming both AMD and Intel motherboards consumes the same amount of power
b. assuming DDR RAM and DDR2 RAM consumes the same amount of power



The X2 4800+ system consumes 198w of power.
The Conroe E6600 system consumes 166w of power.

The Conroe CPU consumes 32w less power than the X2 4800+ CPU. This means the E6600 consumes 64w of power.


The chart comes from this French review of Conroe.

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CORRECTION: Some bad math comparing Conroe E6600 and X2 4800+ total system power consumption. The difference is 32w (198w - 166w), not 22w as originally posted.

jaguarskx, thanks for the extremely informative post. Definitely makes my buying decisions a little easier.

I hear you Pengwin, I'll be sticking w/ the Antec combo(sonataII w/ 450) Just click the buy button on the B stock offered by Antec themselves. Seems like w/ the case, a large CPU heaksink might be an issue. What would be a good choice of a heatsink for the conroe setup? Thanks!

I just realized the 450 the comes w/ the Sonata II is only atx 2.0 compliant. Are the boards that work w/ Conroes all 2.2? If that's the case, looks like my search continues.

You don't have to worry. The biggest difference between an ATX 2.0 and ATX 2.2 power supply is the efficiency rating. Efficiency does not affect how well the PSU will work, but it does affect how much power it will draw from the AC outlet.

The higher the efficiency the less power is wasted. For example, the Antec Sonata case comes with an Antec SmartPower 450w PSU. It is rated at 70% efficiency. Say your when you are playing games on your PC all the components combined will draw 200w of power. You don't need to worry, your power supply will provide 200w to your PC. But because it is only 70% efficient some of power drawn from the AC outlet is wasted as heat. How much power is wasted? That's easy to figure out:

200w / 0.7 = 286w

286w is being drawn from the AC outlet by the PSU. The components only needs 200w, though so the rest, 86 watts, is wasted as heat.

Let's say that for a PSU to be ATX 2.2 compliant, it must be 80% efficient. That means less electricity will be wasted as heat. How much?

200w / 0.8 = 250w

Only an extra 50w of power is wasted instead of 86w. The PC will not care how much power is "wasted" as long as the PSU can provide the power it needs.

How efficient a PSU is, is actually a bit more complicated. But the above are the basics. The most efficient PSUs are rated at 85%.

yeah...they do.