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General discussion

PSU Enough Power?

Feb 27, 2015 3:48AM PST

I want to do a new build soon with 2 Opteron 6272's, a supermicro H8DG6-F, a few fans along with 2 HDD's and one SSD. The extreme PSU calculator says around 738W peak usage (so 100%) and 690W at about 90%. In light of all of this, would I be able to get away with this 750W PSU: http://mypccase.com/sppor75at23s.html

Would that be cutting it too close? I'm open to suggestions.

Discussion is locked

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Let's say you take your every day car
Feb 27, 2015 4:06AM PST

And yes, it can go 120MPH. Take it to a race track and how many laps will it go till something gives? Now back at 60, how long till something fails?

Same idea here. If you want reliable systems you tap the PSU for about 50% of it's max rating.

Another reason is that some PSUs when they fail, do so catastrophically. http://www.tomshardware.com/forum/304723-28-system-components is one of 100's of posts about this.

My designs run 50 to70% of max. And if I have the time I hook up a P3 Watt meter and want to see under 50% of the PSU rating.
Bob

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You said ....'too close' and I agree.
Feb 28, 2015 7:44AM PST

I want enough headroom to handle now plus some expansion and any loss of power due to aging component performance. And sometimes MORE power doesn't cost that much more as you can often find highly rated 850W 900W or 950W units that are only $5, $10, $15 or $20 more and that's usually not enough to break the bank/budget and gives you the headroom/reserve that be useful now or later.

Start with your budget for a good quality PSU and see what good quality units are within that range of tolerance above that after any discounts and rebates.

Let us know how it turns out.

VAPCMD

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On the hunt
Mar 4, 2015 3:43AM PST

I postponed my progress for a second to more thoroughly filter my options and to finish a huge amount of school work. Thanks for the fair warnings Happy I'll definitely look for something closer to the 1000W range now.

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(NT) Ok....let us know how it works out.
Mar 4, 2015 6:18AM PST