How many watts PSU for the following system?

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Dunno7

n00b
Joined
Jul 31, 2015
Messages
45
MSI Gaming M3
Corsair Vengeance 2 x 8 gb
GTX 1070
Skylake 6600k
3 HDDs + 1 SSD
DVD-RW

Possibly add more drives later and overclock
 
What are the good brands? I don't think I have a great selection in my country. We've got Zalman, Chiefic, Thermaltake, FSP (I had one before. It was 500 watts. It killed 4 videocards before the warranty was out and I RMA'ed them all hahahaha), Corsair (I'll never buy anything from this company after their crappy chassisis and GS700 PSU) Courgar, Aerocool, Cooler master. That's it
 
There are many among the horde that disagree with me, but I am a firm believer that the PSU is the place that most mistakes are made. A PSU is most efficient at a 50% load so if the calculator says your system will draw 400 watts I would recommend an 800 watt unit. I have built over 50 high-end CAD workstations over the last 5 years using exclusively Corsair AX or HX series PSU's and have not experienced a single failure. The old saying "You Get What You Pay For" is definitely true when it comes to PSU's.
 
jrweis said:
There are many among the horde that disagree with me, but I am a firm believer that the PSU is the place that most mistakes are made. A PSU is most efficient at a 50% load so if the calculator says your system will draw 400 watts I would recommend an 800 watt unit. I have built over 50 high-end CAD workstations over the last 5 years using exclusively Corsair AX or HX series PSU's and have not experienced a single failure. The old saying "You Get What You Pay For" is definitely true when it comes to PSU's.
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I agree with your principle but not your metric.

Anything 80+ up to gold/plat should meet or beat the required efficiency over the entire 20-80+% range of load. Either platinum or titanium (I forget) requires the efficiency to be met from 10-90+% which helps if you don't mind the price premium.
If you check sites that do the real tests most PSUs curve between 20-80+% is pretty flat, the benefit does not always peak at 50% and often is within the margin of error of the test.

Ideally you want a system that hovers around 20% idle and does not exceed 80% at full load. In practice this is actually pretty hard because:
1) People vastly overestimate their full load, shitty web calculators with lots of padding/worst case guessing don't help.
2) Idle draw on new builds can be very low since cpu and especially gpus have improved low power states a lot in the last 5 years.

With all this in mind, targeting 50% is likely not the best method to use anymore as you are almost always going to have an idle load that is undersized. I would be more realistic and say aim for something like 80%, unless you truly plan to add another video card (SLI is dead, Jim) or similar massive power-sucking upgrade later. (or not: buy once, cry once)
 
Supplies tend to degrade a bit over time as well. I tend to shoot for between a 50-75% rated load myself. Also, having a good bit of headroom for upgrades used to factor in more, but the trend in components these days has been for greater efficiency and less current draw. Good, clean and STABLE power delivery isn't something you should skimp on if you are a [H] enthusiast though - especially if you are into overclocking.
 
criccio said:
Parts are much more power efficient than they have ever been.
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Correction: mainstream parts have gotten much more efficient. Enthusiast parts are as power hungry as ever, maybe even more so. No, the GTX 1080 is not enthusiast because it is the small die part, not the big die. nVidia has done a good job tricking people into buying mainstream parts for enthusiast prices, and then pricing enthusiast parts to the moon.

Dunno7 said:
What are the good brands? I don't think I have a great selection in my country. We've got Zalman, Chiefic, Thermaltake, FSP (I had one before. It was 500 watts. It killed 4 videocards before the warranty was out and I RMA'ed them all hahahaha), Corsair (I'll never buy anything from this company after their crappy chassisis and GS700 PSU) Courgar, Aerocool, Cooler master. That's it
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Out of that list, only Corsair is consistently at least good, and most of their PSU line is above average. Coolermaster, Thermaltake, Cougar, and FSP are hit and miss depending on the model. The rest aren't worth considering.

jrweis said:
There are many among the horde that disagree with me, but I am a firm believer that the PSU is the place that most mistakes are made. A PSU is most efficient at a 50% load so if the calculator says your system will draw 400 watts I would recommend an 800 watt unit. I have built over 50 high-end CAD workstations over the last 5 years using exclusively Corsair AX or HX series PSU's and have not experienced a single failure. The old saying "You Get What You Pay For" is definitely true when it comes to PSU's.
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That is quite literally one of the stupidest things you can do when deciding on what PSU to buy. You should aim for 80-90% at peak load because 99.9% of the time you will not be operating at peak load. If you buy a PSU that covers 90% peak load, then you are around 50-80% while gaming, and 15-25% while idling. However, if your peak load is 50% of the PSU, you are at 30-45% load while gaming, and under 10% at idle. You will never take advantage of that magical 50% load efficiency, and your idle efficiency will be atrocious.

More watts does not mean higher quality.
 
Wyodiver said:
This should help you out:

http://www.coolermaster.com/power-supply-calculator/


Wyo
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I would stay away from that calculator. Its completely wrong. If you have i7-7700k clocked at 5ghz and 2x Titan XP, you require more than ~600W. First of all, nvidia rate Titan XP as using 38 amps on the 12V rail on full load. If you do a stress test with 2 of them you could harm your system seriously. I would get a 1000W or at least a PSU with 80amp on the 12V rail. Now, if you never stress tested, you may be okey, but is that really a chance anyone would take?
 
Frameless said:
I would stay away from that calculator. Its completely wrong. If you have i7-7700k clocked at 5ghz and 2x Titan XP, you require more than ~600W. First of all, nvidia rate Titan XP as using 38 amps on the 12V rail on full load. If you do a stress test with 2 of them you could harm your system seriously. I would get a 1000W or at least a PSU with 80amp on the 12V rail. Now, if you never stress tested, you may be okey, but is that really a chance anyone would take?
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You're the one that's wrong.

nVidia's rating is for the entire system. There is no GPU on the planet that can consume 456 watts on its own. Even overclocked on water with voltage increases, the most power hungry GPU will pull down at most 350 watts (disregarding dual GPU on single board, those count as two GPUs). Beyond that, you need liquid nitrogen cooling as well as pushing voltages to unsafe levels.

There is only one card that got near 450 watts, and that was a Fury X on Furmark with settings tweaked for maximum power consumption. That card hit 432 watts. In normal use case it maxed at 280 watts and averaged 250 watts.
 
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Tsumi said:
You should aim for 80-90% at peak load because 99.9% of the time you will not be operating at peak load.
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I'll add on caveat to that. If you value silence you many want to oversize at the cost of efficiency for reduced fan noise. Though you probably could also just go with a fan-less/silent or get a better case.
 
Unter Dog said:
I'll add on caveat to that. If you value silence you many want to oversize at the cost of efficiency for reduced fan noise. Though you probably could also just go with a fan-less/silent or get a better case.
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That is actually not really true, since most PSUs run the fan based on internal temperature rather than load. A 1000 watt and 600 watt PSU would generate the same amount of heat if they are both 90% efficient at 400 watts. The 1000 watt might have a slight benefit in a larger heatsink, but the difference would be marginal.
 
Tsumi said:
That is actually not really true, since most PSUs run the fan based on internal temperature rather than load. A 1000 watt and 600 watt PSU would generate the same amount of heat if they are both 90% efficient at 400 watts. The 1000 watt might have a slight benefit in a larger heatsink, but the difference would be marginal.
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Fair enough, though Corsair will spec fan speed versus percentage of load, so it is possible. Yes i know its not that dumbed down, but i would bet its close.

From Corsair: http://www.corsair.com/en-us/blog/2014/may/axi_fan-speeds It is very situational.

I will note i design high temp (105C/125C) switching power supplies and get to see warranty data so i am inclined to oversize my power supplies.
 
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I'd say, with the 'k' processor which you will be probably OCing, 500W from a quality device (Seasonic, XFX Core, maybe Corsair, Superflower, maybe there are other - check reviews because every vendor has a great one and a bad one).

550W would be ideal IMHO. Don't bother with 600, go 800 if you want more plus a great deal of headroom.

Edit: go single rail, with a hefty 12V rail.
 
Unter Dog said:
Fair enough, though Corsair will spec fan speed versus percentage of load, so it is possible. Yes i know its not that dumbed down, but i would bet its close.

From Corsair: http://www.corsair.com/en-us/blog/2014/may/axi_fan-speeds It is very situational.

I will note i design high temp (105C/125C) switching power supplies and get to see warranty data so i am inclined to oversize my power supplies.
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Highly situationally dependent. Also, I highly doubt you are going to hear a 1200 RPM PSU fan that is pojnted down and away from you in most cases over your game.

michalrz said:
I'd say, with the 'k' processor which you will be probably OCing, 500W from a quality device (Seasonic, XFX Core, maybe Corsair, Superflower, maybe there are other - check reviews because every vendor has a great one and a bad one).

550W would be ideal IMHO. Don't bother with 600, go 800 if you want more plus a great deal of headroom.

Edit: go single rail, with a hefty 12V rail.
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Single rail vs multi rail does not matter in quality PSUs. If you are overloading a rail in a modern quality multi rail PSU, you're doing something wrong.
 
Tsumi said:
That is actually not really true, since most PSUs run the fan based on internal temperature rather than load. A 1000 watt and 600 watt PSU would generate the same amount of heat if they are both 90% efficient at 400 watts. The 1000 watt might have a slight benefit in a larger heatsink, but the difference would be marginal.
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Most PSUs I've seen had different fan speed vs load curves for different wattage models. That's why I also like to buy bigger ones that will stay in the silent range for the most of my use.

Tsumi said:
Highly situationally dependent. Also, I highly doubt you are going to hear a 1200 RPM PSU fan that is pojnted down and away from you in most cases over your game.
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Oh, they can get plenty loud and annoying.
 
Meeho said:
Most PSUs I've seen had different fan speed vs load curves for different wattage models. That's why I also like to buy bigger ones that will stay in the silent range for the most of my use.


Oh, they can get plenty loud and annoying.
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Again, most, if not all modern quality PSUs scale fan speed based on internal temperature and not a set load curve. The larger PSUs can have a slight benefit from larger fans, but if quiet is your goal, a more efficient PSU (and less heat loss) will be more beneficial.

I did not notice a difference in PSU noise going from an 80+ silver Seasonic M12D to my current 80+ gold Coolermaster V1000. Just because they can get loud doesn't mean they do.
 
Yes, but more powerful PSUs have beefier components heat up less and/or are more resistant to heat, hence lower fan speeds for the same load, all else being equal. I've noticed a huge difference going from 450W to 650W of the same model. One was unbearable even with headphones, the other one silent, because the load didn't trigger its fan ramp up.
 
Tsumi said:
Single rail vs multi rail does not matter in quality PSUs. If you are overloading a rail in a modern quality multi rail PSU, you're doing something wrong.
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I have a follow up question, sorry for the threadjack: I thought that split rails aren't that great when you have low wattage to begin with, like, say, 450-500.
I was convinced they are a safe choice from 800 upwards.
Is this not the case with DC-DC (modern)?
 
michalrz said:
I have a follow up question, sorry for the threadjack: I thought that split rails aren't that great when you have low wattage to begin with, like, say, 450-500.
I was convinced they are a safe choice from 800 upwards.
Is this not the case with DC-DC (modern)?
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99% of modern quality multirail PSUs are actually single rail PSUs with OCPs for sets of connectors. What happened in the past (specifically PC Power & Cooling I believe, who then tried to spread the myth of single rail superiority to repair their image) is that the connections weren't properly distributed on the OCPs. For example, a 600 watt PSU could have two 300 watt rails, but put all of the peripheral connectors on one rail and the CPU, GPU, and motherboard connectors on the other. That set will get overloaded while the peripherals were underloaded. Nowadays in modern multirail configurations, typically each set of two GPU connections would get its own rail, the CPU would get its own, and motherboard and peripherals would be combined. Basically, the connectors are distributed such that if you use them as is, you won't overload any OCP rail, and the OCP rail offers an additional level of protections.

Now, there are a few true multirail PSUs, like the Corsair HX1000 (literally two 500 watt PSUs in one), but those are extremely rare.
 
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Tsumi said:
You're the one that's wrong.

nVidia's rating is for the entire system. There is no GPU on the planet that can consume 456 watts on its own. Even overclocked on water with voltage increases, the most power hungry GPU will pull down at most 350 watts (disregarding dual GPU on single board, those count as two GPUs). Beyond that, you need liquid nitrogen cooling as well as pushing voltages to unsafe levels.

There is only one card that got near 450 watts, and that was a Fury X on Furmark with settings tweaked for maximum power consumption. That card hit 432 watts. In normal use case it maxed at 280 watts and averaged 250 watts.
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I was looking thru this and saw that to alot of people look at psu requirments and believe they need a much higher one thinking the gpu can consume all the power it list but dont read it says for entire system. To op maybe you should look at stores local or sites you shop at maybe list them to us so we can see what exact models you have to choose from.
 
Realistically, OP's system will have a hard time drawing 300W. It will idle at around 70W or less. Sub-100W including a monitor.
 
Tsumi said:
99% of modern quality multirail PSUs are actually single rail PSUs with OCPs for sets of connectors. What happened in the past (specifically PC Power & Cooling I believe, who then tried to spread the myth of single rail superiority to repair their image) is that the connections weren't properly distributed on the OCPs. For example, a 600 watt PSU could have two 300 watt rails, but put all of the peripheral connectors on one rail and the CPU, GPU, and motherboard connectors on the other. That set will get overloaded while the peripherals were underloaded. Nowadays in modern multirail configurations, typically each set of two GPU connections would get its own rail, the CPU would get its own, and motherboard and peripherals would be combined. Basically, the connectors are distributed such that if you use them as is, you won't overload any OCP rail, and the OCP rail offers an additional level of protections.

Now, there are a few true multirail PSUs, like the Corsair HX1000 (literally two 500 watt PSUs in one), but those are extremely rare.
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Thank you very much sir.
 
jrweis said:
There are many among the horde that disagree with me, but I am a firm believer that the PSU is the place that most mistakes are made. A PSU is most efficient at a 50% load so if the calculator says your system will draw 400 watts I would recommend an 800 watt unit. I have built over 50 high-end CAD workstations over the last 5 years using exclusively Corsair AX or HX series PSU's and have not experienced a single failure. The old saying "You Get What You Pay For" is definitely true when it comes to PSU's.
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As mentioned by Aluminum, that might have been true a decade ago but its not true today. Efficiency ratings today require efficiency thru out the whole range. And he should buy more than he actually needs if he's going to keep X psu for over 5 years because they can and will degrade. Sometimes power drops off by as much as 20% of peak power.
 
thesmokingman said:
As mentioned by Aluminum, that might have been true a decade ago but its not true today. Efficiency ratings today require efficiency thru out the whole range. And he should buy more than he actually needs if he's going to keep X psu for over 5 years because they can and will degrade. Sometimes power drops off by as much as 20% of peak power.
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With today's mid to high end power supplies carrying 7 to 10 year warranties, I would expect them to not degrade for at least that long. If they do degrade, that's what the warranty is for.
 
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