I purchased a used HP Proliant DL380p Gen 8 off eBay. It has dual redundant power supplies, both at 750 watts. Doing the math, I realize that if both PSUs are at peak load, they will pull 12.5 amps on a standard 120 volt circuit. Given that standard outlets can handle 15 amps, but are technically supposed to only use 80% of that due to electrical code, that would mean an outlet shouldn't supply more than 12 amps of power total. I also have a mini fridge that uses 0.8 amps plugged in on this circuit.

Additionally, I've read some articles that say the power draw of a server is based on the components inside it rather than the PSU's rated wattage. In that case, I have 2 Xeon E5-2640 v2 8 core processors (16 cores total, each of the two processors having a TDP of 95 W), 32 gigs of DDR3 ECC ram (8 4 gig sticks), 2 10k SAS hard drives, 2 enterprise class SSD's, and all the standard integrated hardware (optical drive, FlexibleLOM ethernet card, integrated P420i raid controller, ILO controller, integrated graphics card, fans, etc). I don't have any PCIe cards or additional hardware installed.

Is it safe to plug both PSUs into a standard outlet? How many watts/amps would the server actually draw at a maximum?

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    Go directly to your favorite shopping web site, look up Kill-A-Watt, and buy now. – Michael Hampton Nov 3 '20 at 21:33

For "is this circuit safe" ask an electrician. Seriously, electrical fires are no joke, and some old wiring is terrifying.

Regarding a rough estimate on draw, that's not how redundant power supplies work. Properly sized, each could carry the load of the system if the other failed. For what that load is, make an estimate with component specifications, such as with the HPE Power Advisor tool. That system is closer to 300W. Probably the 460W power supply would be more efficient, oh well.

As you have this hardware, measure yourself. Get metered PDUs, and check what the draw is from each supply.

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