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Resolved Question

Help with selecting a Power Supply

Jan 12, 2015 3:39PM PST

So Ive not built a PC in years and Im pricing a computer build. Just baffled by what size PS i should buy.

This build will have:
MSI GeForce GTX 970 GAMING 4G Video Card
Intel Core I5 4690K 3.5GHz Processor
MSI Z97-GAMING 3 ATX Motherboard
Kingston HyperX Fury Red 16GB

So far thats as far as I have gone on my planning and purchasing. I think with that video card it would be overkill to go the SLI route.

Any help on a power supply would be great.

From what I gather the onboard sound should be good enough...so no power drain there.....Im not planning on running any LCD displays on the tower etc. (Had one on my last build 8 years ago and it was more novelty then anything)


Thanks in advance. (Im not as smart as I used to be do to a severe head injury so please keep that in mind lol)

Discussion is locked

Grunt11B has chosen the best answer to their question. View answer

Best Answer

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Link, comment
Jan 12, 2015 11:50PM PST
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About too big a PSU. Myth.
Jan 13, 2015 12:16AM PST

There are studies (Tomshardware for example) where the efficiency of the PSU drops as it nears full load. Yes, it's not efficient as very small loads such as 1% of full load but there is that myth that needs some debunking. Toms does that well.

My concern is that too many PSUs fibbed about the rating so to avoid that and get away from PSU caused reboots and short life spans the 50% of load rule is great when you can follow it.

More at http://www.tomshardware.com/reviews/psu-high-end-efficient-platinum,3885-7.html where you can see efficiency at 20, 50 and 100%.
Bob

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Thanks!
Jan 13, 2015 12:25AM PST

ok...thanks for the help everyone. I will poke around and look for a good 600w PSU.

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Yeah, I think 600w...
Jan 13, 2015 4:15PM PST

would be a good start.

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Think I found a PSU
Jan 13, 2015 8:29AM PST

So i read the review on the coolermaster 600 gold ....
Went about looking for it and couldnt find one....found this though and going to pull the trigger. I realize i need some extra power for optical drive and hdd...not looking at a blu ray player as of yet so ill just get a dvd drive...not sure how many pc games come on blu ray...but ill leave that option open. And deffinatly going to get 2, 2TB HDD'S.....maybe a SSD

Think that PSU will work or will it be a waste?

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Answer
Psu
Jan 12, 2015 11:26PM PST

500w or bigger....single rail.

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A 500w wont be eaten alive?
Jan 13, 2015 12:04AM PST

Hmmm I was thinking I would need a bit more then a 500w. My last build granted it was years ago was running an AMD dual core, twin 8800 gtx's in SLI. (Granted it also had a small lcd fan control, sound card) That was years ago....I do know 8800s were power hogs...but it was running an 850w.

I was always told if you get too big of a PS and your not using all of it its just as bad if not worse then over working it.

Anyone have any comments on my current purchase list or improvements? So far the only things purchased are the Mobo,processor (tiger direct bundle with fans and heatsink) and RAM. Still need to find a good gaming OS,
Tower...possible sound card