new build Overkill PSU - is it ok?

[Nysh]

Hello, I’m building a new PC with 13600k CPU and 4070 ti GPU, AIO cooler, RGB fans and stuff, mainly used for gaming. I know the recommended wattage is 750 but I prefer to add a little extra, just to have more room if I want to add some components or for future upgrades.

I’m looking for Corsair RMx series, since I already have sleeved Corsair only cables.

I’d like to buy an RM850x but currently (at least in my area) it’s a little more expensive than RM1000x with way longer shipping times. 
So, is an overkill PSU like 1000W any bad? I know it could be less efficient than 850W for my build but I’m more concerned about fan noise and heat and possible damage to other components. 
 

Should I buy the RM1000x or I’d rather wait for better selling options for 850?

 

Thanks for the help!

[seon123]

In general, a higher wattage PSU could have a louder fan profile (louder at any given load), a higher minimum fan RPM and a higher damage potential before it shuts down (for PSUs that lack multi rail OCP). Whether or not any of these apply depends on the PSU model. For the RMx 2021 specifically, the RM1000x is a bit quieter than the RM850x. 

[Tegneren]

Its a bit overkill for the current system, yes. But you will not hurt anything by going over what you need. Other than maybe the bank account.

You can also consider a PSU with native 16(12+4) pin 12vhpwr. That way you dont have to deal with adapters. I dont know availability or price for them currently

[PDifolco]

44 minutes ago, Nysh said:

Hello, I’m building a new PC with 13600k CPU and 4070 ti GPU, AIO cooler, RGB fans and stuff, mainly used for gaming. I know the recommended wattage is 750 but I prefer to add a little extra, just to have more room if I want to add some components or for future upgrades.

I’m looking for Corsair RMx series, since I already have sleeved Corsair only cables.

I’d like to buy an RM850x but currently (at least in my area) it’s a little more expensive than RM1000x with way longer shipping times. 
So, is an overkill PSU like 1000W any bad? I know it could be less efficient than 850W for my build but I’m more concerned about fan noise and heat and possible damage to other components. 
 

Should I buy the RM1000x or I’d rather wait for better selling options for 850?

 

Thanks for the help!

There's no real downside to a higher power PSU on a given model (except price usually); a PSU provides the power required, not more, and higher wattage ones are overall more efficient

So go for the 1000W model

[mariushm]

A higher wattage psu will be less efficient at very low loads ex 2-5% ... for example let's say your computer idles at 30w or so, and you leave it like that over night. 

The 1000w psu may only be 60% efficient, while a 550-650w psu may be 75-80% efficient. 

Of course that translates in very little extra power wasted, like maybe a few dollars if you leave the pc running idle each night all year, so it's not really a big deal. 

 

 

[Coaxialgamer]

If anything, that system will be more efficient: peak efficiency is around 50% usage, which you'll be closer to with that RMX1000 unit. Efficiency is only a concern if you were running a 200W system with a 1000W PSU or something, and even then more powerful units tend to have higher baseline efficiency anyway.

 

Component sizing means you'll also get a longer lasting, quieter-running unit too.

 

Go for it.

[Nysh]

5 hours ago, seon123 said:

In general, a higher wattage PSU could have a louder fan profile (louder at any given load), a higher minimum fan RPM and a higher damage potential before it shuts down (for PSUs that lack multi rail OCP). Whether or not any of these apply depends on the PSU model. For the RMx 2021 specifically, the RM1000x is a bit quieter than the RM850x. 

So in terms of noise it’s a win for the 1000, thank you. 

But what do you mean with “higher damage potential before it shuts down”?
 

5 hours ago, Tegneren said:

Its a bit overkill for the current system, yes. But you will not hurt anything by going over what you need. Other than maybe the bank account.

You can also consider a PSU with native 16(12+4) pin 12vhpwr. That way you dont have to deal with adapters. I dont know availability or price for them currently

Currently there are no Corsair model with native 12vhpwr pin but there is a cable from Corsair that connects 2 8-pin from the PSU to the 12vhpwr of the GPU that kinda solve the problem of the ugly nvidia adapter 

[HumdrumPenguin]

5 hours ago, Nysh said:

Hello, I’m building a new PC with 13600k CPU and 4070 ti GPU, AIO cooler, RGB fans and stuff, mainly used for gaming. I know the recommended wattage is 750 but I prefer to add a little extra, just to have more room if I want to add some components or for future upgrades.

I’m looking for Corsair RMx series, since I already have sleeved Corsair only cables.

I’d like to buy an RM850x but currently (at least in my area) it’s a little more expensive than RM1000x with way longer shipping times. 
So, is an overkill PSU like 1000W any bad? I know it could be less efficient than 850W for my build but I’m more concerned about fan noise and heat and possible damage to other components. 
 

Should I buy the RM1000x or I’d rather wait for better selling options for 850?

 

Thanks for the help!

I have a 1300W PSU for my rig (AMD 7700x + RTX 4090), and the PSU fans don't even turn on. Aside from not reaching max efficiency, I don't see why you'd be concerned about going with a higher wattage PSU. Think of those people with 1600W models. Unless they're running liquid nitrogen for extreme overclocking, there's no way they're hitting max efficiency either (and even then I'd still have my doubts...). Just remember that you'll need to purchase separately the 600W cable from Corsair if you don't want the shitty dongle coming out of your GPU.

[Nysh]

2 hours ago, HumdrumPenguin said:

I have a 1300W PSU for my rig (AMD 7700x + RTX 4090), and the PSU fans don't even turn on. Aside from not reaching max efficiency, I don't see why you'd be concerned about going with a higher wattage PSU.

So it’s just a matter of efficiency but as other users said it shouldn’t be a big deal in terms of money on wasted energy. 
I’m not that much into power and electricity ahah that’s why I asked for any other problem beyond efficiency. 

 

2 hours ago, HumdrumPenguin said:

Just remember that you'll need to purchase separately the 600W cable from Corsair if you don't want the shitty dongle coming out of your GPU.

Already bought this one

 

[seon123]

4 hours ago, Nysh said:

But what do you mean with “higher damage potential before it shuts down”?

The higher the wattage, the more power it can deliver before the protections kick in. For a PSU that lacks multi rail OCP, that's the difference between sending e.g. 550W down a SATA cable before shutting down or sending 1000W down a SATA cable before shutting down (for a 550W and 1000W PSU respectively)

[Beerzerker]

I agree with all the above and personally I'm running a 1600W unit in this system - Been running it for at least 5 years now with zero issues to even mention as of now. 

All the wattage rating means is the wattage it's rated for is available if it's ever needed and nothing else.

PSU's do not cram wattage into the system, instead it simply provides what the system needs at any given moment in time if it's capable per wattage rating/capacity.

The real benefit of a larger unit is the PSU in use will have an easier life overall and that in turn helps to increase (But it does not guarantee) a longer life for the unit since anything can fail for any reason.
If a unit is running hard all of it's life based on it's wattage capability, chances are it's not going to have a long, happy life but if the unit isn't being stressed to the limit everytime you fire it up, it will tend to last longer and perform better over the course of it's life which is better for everything anyway.

That also helps in situations when you'd want to do an upgrade later of your GPU for example and it's a GPU unit with a higher wattage draw you're wanting to get - The higher rated unit should handle it without the worry of getting a replacement PSU just because you're upgrading the GPU, provided the upgrade doesn't come with a massive increase in wattage required just to run it.

Not to mention a higher rated unit will handle sudden power spikes/loads more easily.

To sum it all up:
Go for it.

[mdk777]

5 hours ago, seon123 said:

The higher the wattage, the more power it can deliver before the protections kick in. For a PSU that lacks multi rail OCP, that's the difference between sending e.g. 550W down a SATA cable before shutting down or sending 1000W down a SATA cable before shutting down (for a 550W and 1000W PSU respectively)

Yeah, no

That is not how it works.

 

That would be a power supply that lacks ALL circuit overpower protection.

 

You would really have to work to find such a unit. 

(not saying it is impossible.... but not any modern reputable PSU)

 

PS, show me a SATA Cable that can handle 550 watts....and then I'll worry about it handling 1000Watts

 

[seon123]

9 hours ago, mdk777 said:

Yeah, no

That is not how it works.

 

That would be a power supply that lacks ALL circuit overpower protection.

 

You would really have to work to find such a unit. 

(not saying it is impossible.... but not any modern reputable PSU)

 

PS, show me a SATA Cable that can handle 550 watts....and then I'll worry about it handling 1000Watts

 

If you are absolutely clueless about even the most basic details about PSUs and their protections, please stop trying to correct others. You are confusing multi rail OCP with OCP in general. OCP is there to trigger if any rail draws more current than its intended to. Multi rail means that e.g. motherboard and peripheral connectors have one rail, CPU has one rail, and each PCIe connector has one rail.

 

Take the Whisper M 850W, a PSU that does have multi rail OCP. 12V1 and 12V2 are rated for 25A, while 12V3 and 12V4 are rated for 40A.

From the protection testing, you can see that OCP triggers on 12V1 and 12V2 trigger at 36A, or around 430W. That means that e.g. a failed SSD could draw about 430W before the PSU recognises a fault and shuts down.

https://www.techpowerup.com/review/bitfenix-bwg850m/10.html

 

For a PSU that lacks multi rail OCP (all of Seasonic's PSUs, Corsair PSUs below the RMi line, all of EVGA's PSUs, etc.), this would not happen, and there is nothing that prevents the PSU from sending all the available current on the 12V rail down e.g. a SATA cable to an SSD, while also obviously catching the SATA cable on fire.

 

In your mind, what is the difference between a PSU that has multi rail OCP and one that does not?

Edited January 18, 2023 by seon123
Something something

[mdk777]

4 hours ago, seon123 said:

If you are absolutely clueless about even the most basic details about PSUs and their protections, please stop trying to correct others. You are confusing multi rail OCP with OCP in general. OCP is there to trigger if any rail draws more current than its intended to. Multi rail means that e.g. motherboard and peripheral connectors have one rail, CPU has one rail, and each PCIe connector has one rail.

 

Take the Whisper M 850W, a PSU that does have multi rail OCP. 12V1 and 12V2 are rated for 25A, while 12V3 and 12V4 are rated for 40A.

From the protection testing, you can see that OCP triggers on 12V1 and 12V2 trigger at 36A, or around 430W. That means that e.g. a failed SSD could draw about 430W before the PSU recognises a fault and shuts down.

https://www.techpowerup.com/review/bitfenix-bwg850m/10.html

 

For a PSU that lacks multi rail OCP (all of Seasonic's PSUs, Corsair PSUs below the RMi line, all of EVGA's PSUs, etc.), this would not happen, and there is nothing that prevents the PSU from sending all the available current on the 12V rail down e.g. a SATA cable to an SSD, while also obviously catching the SATA cable on fire.

 

In your mind, what is the difference between a PSU that has multi rail OCP and one that does not?

TLDR: Conclusion from the bottom

 

So, in conclusion

Since by international agreement, since no single wire output may exceed 240 watt,

 

The difference between a 500 watt, a 1000 watt and a 1600 watt PSU is totally irrelevant.

This is what I stated in my first post.

Perhaps you are the one who should stop spreading FUD.

 

 

 

 

 

 

 

So, you think the entire electronics industry over the last what??  70 years?  designs wire insulation to be a fire hazard?

 

Tell me the melting point of the SATA CABLE connection?   is it 36A?  63A? or perhaps something  less than 5A?

 

I'll wait for your reply.

 

Your premise is that somehow a SATA CABLE will carry enough wattage for long enough to be a fire hazard.

It will not.

The insulation will not catch on fire.

The wire will melt and break the connection long before any fire hazard occurs unless you are running your computer in an environment with 98% oxygen and 2% hydrogen gas.

 

Your entire concern is a red herring. You are not looking at the entire system.

 

The entire history of home computers proves that you are not very well informed. IF...IF  this were an actual concern....you would see reports of home fires started by home computers.

 

Find that on a list of insurance company home accident lists.

You will not. 

 

Why? because it almost never happens. (When it does it is because of other environmental factors(flammables, homeowner circuits, shorts at the wire going to the computer, free basing cocaine, running a meth lab, etc.etc. .      .... the PSU OCP setting is not on that list of contributing factors)

 

In your mind, what is the difference between a PSU that has multi rail OCP and one that does not?

 

 

Marketing.

 

 

In real life, it has no bearing on safety.

Perhaps  a short explanation from an industry source will make this clearer:

 

http://dynapowerusa.com/difference-between-single-rail-and-multiple-rail-power-supplies/

 

Most AC-DC and DC-DC power supplies have internal current protection circuits to protect the power device and the majority of Over Current Protection (OCP) circuits include an automatic recovery feature. Power supplies that have only one OCP circuit are called “single-rail” while the power supplies that have more than one OCP circuits are referred to “multiple-rail”.

The IEC 60950-1 (International Safety Standards for Information Technology Equipment) states that no single output wire in computer power supplies can carry more than 240W. Based upon this standard, the ATX12V specification includes a requirement for an OCP circuit to shut down any rail that pulls more than 240W.

In general, each rail is a set of combined outputs that are tied to a common OCP. At +12V output, 240W translate into a current of 20A (240W/ 12V) on any single wire. However, this relatively low limit would prevent power supply manufacturers from building higher wattage units for computer system with high +12V output. So they came with the idea of breaking down the +12V output into two or more sets of wires, each set of wires with its own OCP. For instance, three sets of wires with an OCP configured at 20A each would triple the maximum allowed power for the +12V output from 240W to 720W.

The +12V power to the motherboard, CPU, SATA, and Molex is usually provided on one rail, with +12V power to PCIe peripherals on subsequent rails. Since the +12V outputs are protected by multiple OCP circuits, there is a need to distribute the +12V loads such that the OCP mechanism doesn’t trip. For example, a particular high-end GPU (Graphic Processing Unit) has a TDP (Thermal Design Power) of 375W. 75W can be drawn from the socket which means that 300W needs to be drawn from the auxiliary PCIe cables of the power supply. The 300W will be provided by 2 x 8-pin auxiliary PCIe connectors rated at 150W each (6-pin PCIe connectors are rated at 75W each). Each of the 8-pin connectors will deliver approximately 12.5A (150W/ 12V). If they were both connected to a single rail which was restricted at 20A, the combined output of 25A would cause the OCP to trip on that rail. Thus, PCIe 8-pin connectors are often on a rail that’s shared only with a PCIe 6-pin connector for a combined 225W, which is under the 240W per the ATX12V specification.

Currently, there are many “single-rail” power supplies with a current rating over 20A on the +12V rail. So how is it possible? The IEC 60950-1 requirement is 240W per wire conductor, so if you get a high current +12V rail and divide it into several wires and make sure no wire will carry more than 20 A, then you meet the restriction.

In summary, the difference between “single-rail” design and “multiple-rail” design is the presence of OCP circuits on the +12V output. Low-end power supplies, however, normally deceive the end-users about the presence of two or more +12V rails. Even though their specification states two +12V rails, but inside the power supply these units only have one OCP circuit and thus these units are in fact “single-rail” products.

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So, in conclusion

Since by international agreement, since no single wire output may exceed 240 watt,

 

The difference between a 500 watt, a 1000 watt and a 1600 watt PSU is totally irrelevant.

This is what I stated in my first post.

Perhaps you are the one who should stop spreading FUD.