Interpretting my kill-a-watt readings

[fancypantsmd]

So I gutted a 4-year-old machine and transformed it into a cheap gaming platform. Despite sticking in a new graphics card (HD 6870) and motherboard (w/ I5/2400), I left in the old Enermax 465W PSU to keep everything within a tight budget.

I just got a kill-a-watt meter and tested the machine while gaming heavily. The "wattage" maxes out at 250W or so. (Note, the "VA" is more like 360, but I don't understand what that is measuring). Does this mean I'm fine? I've read I'm supposed to add on another 25% for aging capacitors, which would raise the wattage up to 312.5, well inside the 465W rating.

Thanks!

 

[popatim]

250w is realtime wattage. The VA reading factors in the phase difference between voltage and current (usefull for calculating the size UPS you might need) and also shows us that this is not a PSU with active PFC.

Capacitor aging is what you subtract from the PSU's rating. so 465-25% = 348w
you are still well inside the theorectical maximum continous output of your PSU.

enjoy your build

 

[clutchc]

Simplified explanation:
VA is Volts X Amps. That is what Watts are (multiplied by the power factor). The power factor is based on loss due to inductive reactance, resistance, and capacitive reactance on the primary (A/C) side of the PSU, which is what you are reading with the kill-a-watt meter.

 

[fancypantsmd]

Best answer selected by fancypantsmd.

 

[fancypantsmd]

250w is realtime wattage... Capacitor aging is what you subtract from the PSU's rating. so 465-25% = 348w
you are still well inside the theorectical maximum continous output of your PSU.

enjoy your build

Thanks! I'm glad I can rely on these measurements. Computer sales guys thought I was nuts for sticking with the 465W, but the proof is in the pudding.