400w silliness

honegod

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My main machine,
a i3 7350k
Strix H270i
1050ti
4 spinners
And 3 120mm fans
Ran fine off a
400 watt Seasonic platinum fanless
For the last few years.

Until it locked up and did max headroom audio.

So a
I7 10700k
Strix Z490i
Arrive tomorrow.
The plan is to use everything else as it was.

The i7 will clearly use more power than the i3 did.
But I am thinking there is enough headroom in the seasonic to work fine.
NO OVERCLOCKING is planned.

Am I missing something obvious here ?

I like the notion of getting more efficiency from the PSU by running it higher in its power range, a factor in choosing 400w in the original build.
 

fist003

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10700k peak is 205w, 1050ti peak is 75w. that's already 280W out of 320W from the PSU (80% of 400W). dunno if the 1050ti has transients issues though
 

honegod

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Thank you.
I do not game on this computer.
It sounds like I can expect the psu to see peaks in the high yellow range.

If I was buying a new psu a 500-600w sounds like a better choice.

Is there anything like cpuid that would keep a running tab on system power draw so I could monitor transient peak load history ?
 

michalrz

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Is there anything like cpuid that would keep a running tab on system power draw so I could monitor transient peak load history ?
The kind of gear PSU reviewers use would be the only sure-fire way. Software won't see some of the more extreme events; even a multi-meter is often not enough to diagnose PSU problems.

That said, you might be able to get away with what you have and not risk things - I mean, it is platinum.
I don't envy you when time comes to troubleshoot any potential problem, though, because you'll need a known good one anyway.
 

motqalden

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A simple wall plug monitor "killawatt meter" is a good way to monitor your total system power usage. Most of them keep track of max load events. Subtract 10% or so from the total due to psu conversion to DC.
 

honegod

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you'll need a known good one anyway
I have an 850 seasonic on hand waiting for the threadripper build that I could swap in, I would like to avoid replacing the 400 if reasonable, hence this thread.
 

honegod

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A simple wall plug monitor "killawatt meter" is a good way to monitor your total system power usage.

I have one of those, sounds like a plan. Thanks.

Thermal readings were new tech to me when I was building this system, I had to rig thermisters wired to digital thermometers to get CPU Temps in my previous build.

So the possibility of onboard software power draw readings seemed worthy of investigation.
 

honegod

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A 500w seasonic platinum fan less is available for about what the new motherboard cost, doable.
That would do the job and restore the headroom the i7 will eat into, but I have been getting flack for "foolishly wasting money" lately and am sensitized.
A 25% boost is great as an improvement but is it just putting a wing on the Yaris ?

Give up a bit of steady state efficiency for a bit of high end stability that might never be used, just to feel good ?
 

T4rd

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10700k peak is 205w, 1050ti peak is 75w. that's already 280W out of 320W from the PSU (80% of 400W). dunno if the 1050ti has transients issues though
That's not how PSU ratings work. The peak output of the PSU is still 400W, it will just draw 480W from the wall to reach that 80% efficiency rating. But OPs PSU is a platinum rating, which is ~90% efficiency, so it would only draw ~440W from the wall at max output.

OP, I think you should be fine still with the 400W PSU using the components in their stock/default configuration. You'll rarely be running the components at their peak TDP and in the rare situations you do you're still only around ~80% of the PSU's capacity, which is fine for any PSU worth its metal. Otherwise you'll be running it idle-light usage at around 100-200W or around 25-50% of the PSU's capacity where it's most efficient. You also said that you will never game on this PC, so the GPU will never use anywhere near that 75W peak as well.
 
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honegod

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OP, I think you should be fine still with the 400W PSU using the components in their stock/default configuration.

I see no reason to disagree, thank you.

Buuut, since I have to tear this down anyway and the next old thing likely to break down is the videocard, and newer generation cards are more power hungry than the 1050ti, Newegg has promised a new 500w replacement to arrive on Wednesday so I can look forward to not stressing this question next time I gotta do a major parts swap.

Besides I might decide to see what doomII, or rtcw looks like on a really big screen.

Seasonic 500w Titanium fanless, incoming
 

Axman

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Don't forget that 400W rating is combined across voltages. What your hardware may draw could exceed, for example, your PSU's 12V rating.
 

honegod

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Don't forget that 400W rating is combined across voltages. What your hardware may draw could exceed, for example, your PSU's 12V rating.
Aye, I am looking at staggering the spinup of the harddrives, as a potential peak flattener, In that vein.
 

Tsumi

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Don't forget that 400W rating is combined across voltages. What your hardware may draw could exceed, for example, your PSU's 12V rating.
For a standard system, peripherals are typically less than 50 watts.
Aye, I am looking at staggering the spinup of the harddrives, as a potential peak flattener, In that vein.
Not worth it for only 4 hard drives. You'll need at least 15 hard drives to make any kind of significant power reduction.
 

Mr Evil

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Don't forget that 400W rating is combined across voltages. What your hardware may draw could exceed, for example, your PSU's 12V rating.
High efficiency PSUs will have the lower voltage rails derived from the 12V rail, and so will be able to supply their entire rating on the 12V rail alone.
 

Axman

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For a standard system, peripherals are typically less than 50 watts.
High efficiency PSUs will have the lower voltage rails derived from the 12V rail, and so will be able to supply their entire rating on the 12V rail alone.

But anything that draws power from 12V through a voltage converter will lower the total 12V output. When you add peripherals and the motherboard, 400W may not be adequate. I've had HTPCs with 400W power supplies, but those were carefully planned PCs with low-power components.

Don't get me wrong, it's a good idea to run a PC as close to its PSUs peak power output for efficiency reasons, but you should also calculate how much power you'll need in advance, not just cross your fingers and hope for the best.
 

honegod

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but you should also calculate how much power you'll need in advance, not just cross your fingers and hope for the best.

That is precisely the intent here.

I see no way to get actual numbers for each new component,
motherboard and cpu, but I presume that both will draw more power than the previous generation.
The cpu looks to be at least double, and I have no faint clue what the motherboard itself uses, what with all the cooling enhancements added it implies more.
A basic fact is that the new board uses only the same two power plugs, with the same ratings, as the old one.
And the 400w has those same outputs.

Swapping in a videocard that adds a whole new power plug is a different matter entirely. That is what I think the 500w will act to resolve.
 

honegod

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Not worth it for only 4 hard drives. You'll need at least 15 hard drives to make any kind of significant power reduction
Thanks.
I had thought about running up to 8, using a nifty m.2 to 5 sata plug module I got, but the stacking scheme for the m.2 drives on this motherboard nixed that.
I will stick with the 4 setup.
 

honegod

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I just tore the computer down.
open air, with no filtration the only furry dust was around the fans, everywhere else had a very light coat.
the psu, under the motherboard, has no visible accumulation at all.
The fanless business worked splendidly in that regard.
 

honegod

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The new setup is up and running on the 400w, I added a 970pro500gb, just cause I could, but I do not like the looks of the cooling. If I figure how to clone the windows install over I will probably swap it for the 960250gb and leave the buried mount empty.
8 threads all boosting at 5000ish.
Still engaged in shakedown trials and the new noctua cooler tugs at my duct building side. But that is for the overclocking and cooling forum.

THANKS all, and ta, until I get the shivers about a 500 running a 5050ti in a year or three.
 

Tsumi

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But anything that draws power from 12V through a voltage converter will lower the total 12V output. When you add peripherals and the motherboard, 400W may not be adequate. I've had HTPCs with 400W power supplies, but those were carefully planned PCs with low-power components.

Don't get me wrong, it's a good idea to run a PC as close to its PSUs peak power output for efficiency reasons, but you should also calculate how much power you'll need in advance, not just cross your fingers and hope for the best.
The primary components OP picked out have a combined power draw of around 300 watts. Add in 50 watts for peripherals and you're still sitting comfortably under 400 watts for peak load.
That is precisely the intent here.

I see no way to get actual numbers for each new component,
motherboard and cpu, but I presume that both will draw more power than the previous generation.
The cpu looks to be at least double, and I have no faint clue what the motherboard itself uses, what with all the cooling enhancements added it implies more.
A basic fact is that the new board uses only the same two power plugs, with the same ratings, as the old one.
And the 400w has those same outputs.

Swapping in a videocard that adds a whole new power plug is a different matter entirely. That is what I think the 500w will act to resolve.
Power draw on the top end components have been increasing, but not as much as you may think. Power draw on midrange components have stayed relatively consistent.
 
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