PC hardware forum: how to calculate the power consumption of each component?

What could a 240W power supply do?

by Magic-wand - 11/13/12 6:28 PM

In Reply to: I'd need to see the PSU by R. Proffitt

That's why I want to know the exact power consumption of each component.

This is a HP 7800dc sff, CPU E8400, 4G DDR2 800Mhz(2 sticks).

I guess motherboard(Intel Q35 Express Chipset) consume about 40W or more, a harddisk and a DVD-RW each 20W, CPU 65W, and DDR2, USB...etc, that is well above the 120W limited, not mention to a PCI-X display card.

I wonder if the power supply could survive when any peripheral card added.

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Exact consumption

by pgc3 - 11/14/12 6:39 AM

In Reply to: What could a 240W power supply do? by Magic-wand

To be EXACT get out your schematic and break out your VTVM preferably a Fluke or similar standard, even then, there will be variables.

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exact power consumption of each component.

by bob b - 11/14/12 4:06 PM

In Reply to: What could a 240W power supply do? by Magic-wand

I'm sure that's possible but it might be beyond we mortals.

Most folks use this thing called 'tdp'........it refers to power.

For a normal system the 2 big power users are the cpu and the gpu.

Folks have their favorite method to determine the proper psu size.

Here's something that seems to work.
Cpu power + gpu power x 2 + 100w.

Best to get a single rail unit.......otherwise you might get into that load balancing non-sense.

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Answer Best answer as chosen by user Magic-wand

efficiency

by bob b - 11/14/12 3:27 PM

In Reply to: how to calculate the power consumption of each component? by Magic-wand

For a psu that refers to how well the unit can convert input power to output power.

Ex.
300w input @ 80% efficiency equals 240w output.

A psu is rated with output power.........often it's wishful thinking.

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