How much extra wattage should I leave when choosing a PSU?

[coolyjojo]

I am trying to pick a power supply for my new low-end build. My estimated power draw is around 325W-360W. I am wondering if it would be safe to go with a 430W PSU or to add some extra leeway with a 500W. I am not sure it the 430W will be able to handle my hardware and have spare wattage in case my PC would need it for some reason. Please help.

 

[Ethanh100]

I am trying to pick a power supply for my new low-end build. My estimated power draw is around 325W-360W. I am wondering if it would be safe to go with a 430W PSU or to add some extra leeway with a 500W. I am not sure it the 430W will be able to handle my hardware and have spare wattage in case my PC would need it for some reason. Please help.

Is that estimated wattage from pc part picker, if it is then try the calculator linked below, as pc part pickers estimate is based off of only cpu draw, gpu draw, and a few other things, it is much lower than you need. Take that recomded wattage from that calculator and maybe add 50w. Then you should be fine for everything and you will be safe to overclock and everything
http://outervision.com/power-supply-calculator

 

[turkey3_scratch]

If you want the best efficiency, it's best to double. However, it's generally reocmmended to get about 30% more. I would go with 500W if I were you, plus it's often difficult finding quality PSUs under $500 anyway. It's nice to have headroom. 550W actually is going to be more ideal, I recommend an XFX TS 550W.

 

[Bearmann]

With bronze to titanium psu's available now from good manufacturers, I don't think you need to double the power anymore. You can have close to 90% efficiency from 20%-100% load (10%-100% with titanium). Ideally, you would want your psu to be at 20% load at idle and about 70% load at max (to leave some headroom for future upgrading), but your computer may exceed that narrow range. There are a lot of choices once you get to 550 watts, so I would choose that and pick something at least tier 3 or better.