I am setting up my gaming rig in my room and the wall outlet is 10 feet too far so I am considering using an extension cord to power my comp. It has a core i7 920 with 6GB ram and a Radeon 5870 powered by a corsair 750watt psu. I looked around in my basement for an extension cord and the only one that I could find was a 3-pronged orange cord @ ~35feet . I looked at the label and it said 1625W, 125V ,13A. Is this enough to power a high end gaming rig?
The main thing I am concerned about is whether it will be able to push enough amperage as my PSU is rated for up to 60A on the 12v rail and the cord just says "13A". I don't know anything about volts and amps(other than V * A = W LOL) so any advice would be appreciated.
EDIT: this cord will be plugged into a powerstrip surge protector with triple 22" LCD monitors as well
The 750Watts PSU will draw a max of 10 Amps at 80% efficiency from the 110VAC outlet. If your outlet is 10 feet away and you want to use a 35 foot extension cord, make sure that the extension cord is not coiled. A loop is fine. A coiled extension cord will create electrical problems.
Since your cord is rated for 13Amps, it will provide sufficient power to your 750 Watts PSU if this is the only electrical load. If you connect the monitors to the surge strip, you must add the Amp draw of each monitor and then obtain the total draw in Amps.
Most probably, the outlet has a rating of 15 Amps and depending on the circuit breaker that supplies power to this outlet and other outlets in adjoining rooms, make sure that you are not overloading this circuit. Take lighting load, speakers, and TV load when you add up all the Amps. Don't forget portable heaters plugged in during winter, and fans in summer.
V x A = Watts in DC circuits - in AC circuits divide V x A by the power factor (0.8)
Since my computer probably only uses 4-500W of power and the average LCD monitor uses 110W that means ~700-850W of total electricity? Even if my computer maxed out at 750W that would be 750W + 3(110W) = ~1.1kW
1.1kW / 125V = 8.8A and with power efficiency factor @80% it would be 11A drawn from the wall. Since my computer doesn't max out its PSU the amount of amperage would likely stay below 10 which would be well within the safe range of my power cord (13A rating)?
Am I doing these calculations right? Would it work to have my triple LCD's connected to the same cord as my computer?
750W + (3)(110w) = 1080W @ 80% eff. = 1350W / 120v = 11.25A. That's assuming 100% load on everything, which will never happen. On top of this, I'm sure those cords are severely underrated for safety reasons.
Actually, that "power factor" thing is not needed. On loads like this the "power factor" is very close to 1.0,
However, estimating the computer's PSU load DOES use the Efficiency of that PSU. Most modern ones have efficiencies around 80%, meaning that 80% of the power drawn from the wall actually ends up being supplied to the mobo and peripherals in the case. Your PSU maxes out at 750 W, which means its max draw from the wall is 750 W/0.8, or about 935 W. Now, to that add the power consumed by the monitors - 3 x 110W - plus anything else on that cord, and you have 1265 W max against a max rating of the cord of 1625 W. No Problemo!
The notes others gave about other loads on the same wall circuit, and how that relates to the breaker rating of 15 A (at 125 VAC that's max 1875 W) are also important to consider, outside of the question of the suitability of that extension cord.