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Question

PSU Wattage

Mar 9, 2020 3:31PM PDT

Hello all, question for you.. I'm having a new computer built and have a question about the size of the psu. This is not a gaming computer, just going to be used for normal home use / streaming movies / watching sports. The build consists of an Intel core i7-9700, ASRock H310CM ATX mobo, 16 gigs of ram along with a 1 TB wd blue m.2 ssd. other than that, just one optical drive ( dvd / cd rw ) three 120 mm fans and one 140 mm fan, a fan controller, older 24" monitor and several 2.0 and 3.0 usb ports. No designated video card. Is a 450 watt power supply sufficient... or should I up it to a 550. I've tried using a few of those PSU calculator's, but not sure how reliable they are.. I get different answers despite entering the same criteria each time. anyway, I feel like 450 is plenty, but would like your thoughts before proceeding.. Thank you in advance for your help with this.

Discussion is locked

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Answer
Needs more detail.
Mar 9, 2020 3:46PM PDT

What is the +12V Amperage rating? Dual rails and it's toast. Single rail and it should be fine.

BUT DO NOT PUSH YOUR PSU HARD. Best is 50% of the PSU max. At most you want to pull 75% of the PSU max and never exceed Amperes on any rail. Not just Watts.

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Answer
I've lost count on how many PCs I've built . . .
Mar 9, 2020 7:25PM PDT

but there's a tried and true rule. Get the biggest you can afford. Go for the 550. Only pennys difference in cost. BTW, don't count the monitor in your calculations. And those calculators are very generic. Don't ask me how I know.

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Keep in mind.....
Mar 10, 2020 10:41AM PDT

if you want to upgrade a component on your computer, a lesser PSU might not suffice and you would have to buy a new PSU anyway. Obviously you don't need to go with a huge PSU (1000W for example) but I agree that the 550W is a much better choice.