PC Partpicker (Estimated Wattage)

JOSHSKORN

Limp Gawd
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May 29, 2007
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How good is PC Partpicker at with estimating the wattage you'll need for your PC?

What I'm getting at is, I put all of my parts in, and it claims I'll need a PSU of just over 500 watts for my setup, and I have a 1000 PSU. I'm wanting to replace my GPU soon. Currently, I have a GTX 980, and I want to upgrade to possibly the RTX 3080 or maybe even RTX 3090. From what I'm seeing, these video cards use almost 200 watts more of power.

Edit: Here are my system specs, as I listed on PCPartPicker. The only thing that isn't accurate is the RAM, I couldn't find 4x16GB listed: https://pcpartpicker.com/user/JOSHSKORN/saved/#view=7PnjZL
 
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pendragon1

Fully [H]
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Oct 7, 2000
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25,284
How good is PC Partpicker at with estimating the wattage you'll need for your PC?

What I'm getting at is, I put all of my parts in, and it claims I'll need a PSU of just over 500 watts for my setup, and I have a 1000 PSU. I'm wanting to replace my GPU soon. Currently, I have a GTX 980, and I want to upgrade to possibly the RTX 3080 or maybe even RTX 3090. From what I'm seeing, these video cards use almost 200 watts more of power.
ive always recommended to use at least the minimum recommended for the gpu. add more if you intend to oc.
 

Tsumi

[H]F Junkie
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CPUs also vary greatly in terms of power consumption, especially when talking about overclocks. Listing only the GPU is less than half of the picture.
 

JOSHSKORN

Limp Gawd
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May 29, 2007
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262
CPUs also vary greatly in terms of power consumption, especially when talking about overclocks. Listing only the GPU is less than half of the picture.
Fixed the OP to include all of the parts in my PC. The only thing missing is the eSata connector to which I don't even use anyways.
 

SmokeRngs

[H]ard|DCer of the Month - April 2008
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I think I put my setup in there one time for an estimate on power usage. It may have not been there but another power usage calculator. What I do remember is the power usage it said for my system was waaaaaaaay off. It probably showed my power usage at 150w or more than what my system uses under the heaviest load. That includes the GPU overclocked and running 100% on a distributed computing program as well as all threads at 100% on my CPU on another distributed computing program. The only thing which might run my CPU harder than a dc program is encoding and maybe Prime95 and neither of them use much more power. The dc program running on my GPU is a different story. Nothing runs that harder. Power usage and temps on that dc program are much higher than any game has ever even thought about using.

Take any power estimate from one of the power calculators with a huge grain of salt. It seems what they do is take the absolute max power something might theoretically use and then add another 10%-20% power usage as a buffer to cover their asses. The system in my sig is running on a Seasonic Focus Gold GX-650 and previously on an ancient Antec NeoHE 650. I can probably count on one hand the number of times either PSU has ever seen anything close to a 50% load much less anything higher. My 650 watt PSUs are serious overkill. It gives me a buffer for higher power components if I get some as well as headroom to avoid being at 100% load.

I could probably replace my RX570 with an RTX 3080 and the PSU wouldn't be an issue. It would be running closer to 100% load than I would care for but it should work fine.

The best thing to do is find out how much power the GPU is probably going to be using which in the case of a 3080 can be 350w+, then add in the max power your CPU is going to use, then add a couple hundred watts for other components and then add a bit more for a buffer. That should give you an idea of what you need in a PSU.

I wouldn't mind seeing how much juice my current system uses in total but I'm too lazy to look for my Kill-a-Watt.
 

johnnysd

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Oct 6, 2007
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203
There is a good Gamer's Nexus video showing that even high end systems (single CPU and GPU) run even under stress at much less power draw than people think, and in general people buy WAY too large of a power supply for their needs especially if it is a quality P/S
 

Bowman15

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There is a good Gamer's Nexus video showing that even high end systems (single CPU and GPU) run even under stress at much less power draw than people think, and in general people buy WAY too large of a power supply for their needs especially if it is a quality P/S

Bingo, if anything they over estimate. Get good quality bronze-gold 650-750W that covers the majority of everything. For a 3090 an 850W bronze should do if worried.
 

TheSlySyl

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I was worried about wattage because I'm considering one of those 300w GPUs in the future. So I got a UPS that shows wattage on a display. (Also there were a few brownouts due to weather recently...)
At the absolute fullest load I could manage with my 3900X, 1080ti (using 250+ watts by itself), 6 hard drives, 4 nvme drives, a bunch of peripherals, etc. - I wasn't able to use over 500 watts total.
 

Tsumi

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I was worried about wattage because I'm considering one of those 300w GPUs in the future. So I got a UPS that shows wattage on a display. (Also there were a few brownouts due to weather recently...)
At the absolute fullest load I could manage with my 3900X, 1080ti (using 250+ watts by itself), 6 hard drives, 4 nvme drives, a bunch of peripherals, etc. - I wasn't able to use over 500 watts total.

500 watts at the UPS on a 90% efficient PSU means your system is actually pulling about 450 watts.

In addition to grossly overestimating, the other thing people often don't realize is that not everything is running at full power at the same time. Hard drives are idling, unused cores are idling, etc. Only a combination of synthetic loads are able to fully max out a system. Therefore, even if the chosen PSU is at the maximum theoretical load of the computer, most users will never approach the maximum load of the PSU.
 

TheSlySyl

[H]ard|Gawd
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500 watts at the UPS on a 90% efficient PSU means your system is actually pulling about 450 watts.

In addition to grossly overestimating, the other thing people often don't realize is that not everything is running at full power at the same time. Hard drives are idling, unused cores are idling, etc. Only a combination of synthetic loads are able to fully max out a system. Therefore, even if the chosen PSU is at the maximum theoretical load of the computer, most users will never approach the maximum load of the PSU.
I forgot that my UPS is also powering a monitor, a (network) switch and my 5.1 surround sound system.
So my actual pure computer power is less than that.
 

johnnysd

Limp Gawd
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Oct 6, 2007
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Seasonic has an awesome power estimator on their website. Even has the latest AMD video cards and processors there

https://seasonic.com/wattage-calculator

Even for a 5900X, 6900XT system with 2 M.2 drives a hard drive and 4 case fans they feel a 529W P/S will be enough and recommend a 650W. Trust me they wouldn't recommend something without enough margin of error that they know will not cause support calls for too little power.
 
Joined
Dec 8, 2016
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Seasonic has an awesome power estimator on their website. Even has the latest AMD video cards and processors there

https://seasonic.com/wattage-calculator

Even for a 5900X, 6900XT system with 2 M.2 drives a hard drive and 4 case fans they feel a 529W P/S will be enough and recommend a 650W. Trust me they wouldn't recommend something without enough margin of error that they know will not cause support calls for too little power.

I like their wattage calc as well, looks pretty solid.
 

travm

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Feb 26, 2016
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Looks to be the same as the Seasonic one with a little different skin.
Just checked, there's a blurb at the bottom of the seasonic page stating just that. Exactly the same thing.
I've been using that for years with no bad results
 

johnnysd

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Just checked, there's a blurb at the bottom of the seasonic page stating just that. Exactly the same thing.
I've been using that for years with no bad results
Oh didn't notice that. Seems to be really accurate and again unless you doing some extreme overclocking you don't really need a very big power supply even for a high end system.
 

travm

Gawd
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Feb 26, 2016
Messages
831
Oh didn't notice that. Seems to be really accurate and again unless you doing some extreme overclocking you don't really need a very big power supply even for a high end system.
Worth noting that as components age they can lose some ability to do their job. Over spec psu is insurance for the future.
 
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