Specing PSU requirement

[bononos]

The Antec 380W review article mentions that it is sufficient for a i7 and a discrete video card (w/o needing a 2nd pcie power connector) which seems on the low side.

http://www.anandtech.com/show/3902/antec-earthwatts-ea-380d-green-380w

I checked using a psu calculator and ~380W looked ok until I choose capacitor aging which increased the need for higher wattage considerably. What do you think?

 

[zCypher]

What's the complete build? Extra hard drives, optical drives, sound cards, fans, etc?

 

[lehtv]

^ this

 

[bononos]

I reentered the calc again for: i5-2500, 2 sticks ddr3, hd6850, 2 sata, 1 dvd-rw, 1 bluray, 1 extra pcie 1x, 2 regular 120mm fans to get recommended size of 361W. Added 20% capacitor aging - 423W

Calculator - http://extreme.outervision.com/PSUEngine

Any comments about the sizing claim in the article?

 

[lehtv]

That's a pretty accurate calculator, maybe a bit underestimating. With the added capacitor aging it's spot on.

TDP for 2500 = 95W (stock)
TDP for 6850 = 127W (stock)
Subtotal = 222W at 100% load

The rest will use maybe 50-75W.
Total ~300W absolute max.

A 430W power supply will be stressed to 70% at absolute max load. In a real life load scenario e.g. 3DMark it will be stressed to 50-60%. Anything more is a bit overkill for your particular setup. If you plan to overclock heavily or upgrade the GPU to something much punchier in the near future, then even 500-600W could be justified.

A 380W power supply would also handle it (60-70% in a real life load scenario), but will allow for almost no room for upgrades or overclocking. Anything less than 380W is not a good idea, it won't last long.