Power Supply Wattage estimates

Your basic noob questions.

  • if PCPP lists my wattage requirements as around 550W, is the site calculating for load, or not

  • do I need to double that in psu terms for a safe operating environment for gaming, or will a 750W do alright?

  • are Fractal Design psu’s well built?

Thanks guys.

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PCPP overestimates to account for load spikes.

Sustained load is much lower and a 500W PSU will be just fine is 9/10 configurations with just a Single GPU if you don’t go HAM on the components.

Please share the PCPP link so we can see what components you are thinking about using because it is a moving target.

I usually over estimate a bit, probably on that order.
Also, I try to plan around what I might add later, which is usually a fair bit; most pcie slots/lanes, ram channels etc.

If you over estimate for safety, perhaps look at the 80 plus “bronze” Platinum or Gold.
Not a lot of difference, jut means it’s less wasteful when at lower usage.

Like, if you made a low power system that ramps up occasionally, like a HTPC that occasionally games or something.

But I presume you already thought of these anyway.

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IIRC they calculate using the max estimated load or the rated TDP of a product. Which in theory should be pretty close to what you’d pull from the wall at 100% load on everything.

No, assuming you’re not doing LN2 overclocking or something. IMO a 650W power supply will cover like 90% of single CPU/GPU systems and a 750W like 98%. The last 2% being FX 9590 and R9 295X systems :slight_smile:

Depends on the model. One of the 80+ Gold or higher units, more than likely yes.



I had a feeling it might be all inclusive estimate, but googling produced a lot of talk of “safety estimates” being 1.5x a product’s TDP, and also the “efficiency” jargon of 50% of a psu’s load being ideal, which would mean spending over 200 gbp on a 1000W IF I could find one right now.

You’re not going to be pulling a sustained 500W unless you have a high-end HEDT CPU with a multi-GPU configuration.

Take a look at this, it is a better calculator then PCPP-
It also sizes UPSs


750W is more then fine for that setup.

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The peak efficiency is way overblown. We’re talking a 3% difference in efficiency between 20/100% load and 50% load for an 80+ Gold power supply. For servers or render farms I can totally understand the reasoning, but for anybody else I don’t believe the cost is worth it.

And I just take the guesstimated system consumption and add 100W to 200W to it and grab a power supply in that range. That way it should have enough for new hard drives or fans or even overclocking.

Also i would like to mention that the Msi MPG Z490 Gaming Plus,
motherboard is a pile of trash.
At least as far as the vrm is concerned.

Thanks for the help guys.
You can go ahead and close.

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