750W PSU pulling 10A@120V

[wongakk7]

Hi there, need some advice on measuring power consumption. I am running a rig at my parent's home and am trying to measure power consumption so I can reimburse them appropriately. I am currently running 3 x rx580, and 1 x gtx 1060. I am using an EVGA 750GQ gold rated power supply. I estimate my power usage should to be around 700W factoring in the efficiency of the power supply.

My father measured the current draw at the wall and found it to be 9.8A. He claims that my rig is pulling 9.8A x 120V = 1176W. Is it possible for a 750W supply to be this ineffecient?

Any advice here would be appreciated.

 

[Scottray]

You're mixing up alternating current input power to the PSU versus the DC power delivered to the PC's components. The 750W spec is the power that can be delivered off of the +12V rail, or about 62A. The power off of the wall socket is alternating current. Since it's sinusoidal, current and voltage are expressed in RMS (root mean squared). As long as your father measured the current in RMS, 9.8A RMS seems reasonable.

To measure the watt hours your rig actually uses, you need a device like this: https://www.homedepot.com/p/Kill-A-Watt-Electricity-Monitor-P4400/202196386

 

[Paperdoc]

Well, the numbers (IF they are all correct) say IF the PSU is actually supplying its max output of 750W to your machine, it is operating at 63% Efficiency. Although that PSU is rated at 90% Efficiency "under typical conditions", any PSU is a bit less efficient when running right at max load.

Is the current measurement instrument accurate? Did you Dad check the Voltage at the same time - we're making an assumption about 120 VAC in the calculations. Is there anything else plugged into the wiring that your Dad measured the current from?