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Question

PSU advice

Sep 18, 2015 2:44PM PDT

Alright, I asked a question on this forums a few days back because my PC started restarting randomly. A helpful person said(using car analogy), "You put on 120 mile per hour (MPH) tires then drive over 400. What happens to the tires?

Here you have at most, under ideal conditions a 240 MPH tire but you are at 400 MPH. Bad things will happen.

-> I don't see where you revealed who the maker was. If it was you well the PSU is completely wrong for this rig. Try another but with a suitable +12V supply. In the link I gave the stress test has some maximums for us to use. One is 296.8 Watts and another is a peak 428.38 Watts.

To even have a chance of working the +12V rail for this GPU alone must be well above the maximum. This +12V feeds the CPU so let's get that plus a few hard drives on line.

I use 20 Watts per HDD.
The CPU looks to be about 88 Watts.

Total peak is about 530 Watts. So your +12V rail needs to be about 45 Amperes. Shop for a new single rail PSU and check those specs."

I am VERY new with computers so I didn't really understand what that meant. Can you guys tell me what PSU I should get for these specs:
Intel Core I7 4790k (stock fan)
EVGA NEX 650W G (current power supply)
GTX 980
Fatal1ty 797 Killer (motherboard)
32 gb of RAM

Discussion is locked

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Answer
I believe you are ok with what you have now.
Sep 18, 2015 11:25PM PDT

From what I see, it says the minimum power require is 500w, and I see you have 650.

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Answer
I think that's a terrible PSU.
Sep 19, 2015 6:58AM PDT

"12V1@20A, +12V2@20A, +12V3@20A" from the specs I found.

These triple and quad rail PSUs tend to be OK until you put in a high end GPU.

I've looked up power for GPUs before and this fails in my view.

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I see this 980 card do use 2-6pin connection,
Sep 19, 2015 8:50AM PDT

which maybe ok for this PSU. Of course we are not talking about future upgrade for now. GPU power requirement is 165w, is that what you saw?

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It's worse than 165 Watts.
Sep 19, 2015 8:59AM PDT

I've looked at 20 Ampere rails (that's 240 Watts max under ideal conditions) and Toms showed the 970/980 peaks to be over 400 so this PSU with it's split rails is not a good idea.

If this was a single rail of 40 or more amperes (that's 480 Watts) then it would be OK but not great. There are far too many posts and pleas for help where the PSU is not following the advice of 50% of the rated load. Yes we can give it a pass at 75% but here the peak draw of the card blew past the rail's capability. That's not good.

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Would this be fine?
Sep 21, 2015 10:47AM PDT

I know that it is the same company but it is 750w and it does have single rail

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I see +12V@62.4A
Sep 21, 2015 1:18PM PDT

So that's 700 Watts total peak available. Since the peaks were 400, I hope you see why this should be fine.

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Thanks!
Sep 21, 2015 1:48PM PDT

I'll be buying that one then Grin

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Answer
This will solve your problem
Sep 30, 2015 6:09AM PDT