8700k and 1080 ti power supply recommendation?

[Melodist]

Hello there,

 

How much headroom you'd recommend for the 8700k and 1080ti / which power supply?

 

I've personally used an EVGA 850 for my 6900k and 1080ti build, what would you recommend?

[NoRomanBatmansAllowed]

Put them into a PCPP build with all your other parts. 

 

Then try to get a relatively high-tier (tier 1 or 2) PSU that's power limit is at least 100W more than PCPP says.

 

[iRileyx]

Assuming you're going to be overclocking the two of them, a decent 650/700 watt.

[1234vietnam]

deleted

[Melodist]

Just now, RKRiley said:

Assuming you're going to be overclocking the two of them, a decent 650/700 watt.

Thanks for your response, I've been thinking the exact same thing. Any power supply you'd recommend straight away?

[iRileyx]

Just now, Melodist said:

Thanks for your response, I've been thinking the exact same thing. Any power supply you'd recommend straight away?

Corsair RMx or Evga G2/G3 are normally my go-to suggestions if price isn't an issue.

If you need something a bit cheaper, a Corsair CXm aslong as its a grey label.

[NoRomanBatmansAllowed]

4 minutes ago, Melodist said:

Thanks for your response, I've been thinking the exact same thing. Any power supply you'd recommend straight away?

Choose something in tier 1 or 2.

 

 

[CrippledROBOT]

12 minutes ago, Melodist said:

Thanks for your response, I've been thinking the exact same thing. Any power supply you'd recommend straight away?

The Seasonic SSR 650 or 750 Platinum series are really good!

[seon123]

An RM550x should be fine, and will be quiet. Plenty of headroom, even assuming overclocking. 

[Stefan Payne]

3 hours ago, Prqnk3d said:

i think a 750 would be fine. i use (GPU+CPU+100)*1.5 to calculate psu wattage.

so (300+95+100)*1.5=742.5

For what?!
What are you thinking?!
And what are you calculating?!

 

3 hours ago, Melodist said:

Hello there,

How much headroom you'd recommend for the 8700k and 1080ti / which power supply?

I've personally used an EVGA 850 for my 6900k and 1080ti build, what would you recommend?

None, so a good quality 500-550W is more than enough.

What are you looking at??

[1234vietnam]

deleted

[seon123]

6 minutes ago, Prqnk3d said:

( GPU TDP - 300W     +      CPU TDP - 95W      +     Motherboard/Storage/Fans - 100W )   *   1.5 To get overclocking headroom, not  put too much stress on the PSU and get better efficiency. 

 

As shown in the image, efficieny is best at 300W out of 750W. 

Do you seriously think that a motherboard, fans and storage will use 100W? Which, btw, according to your numbers is more than the CPU? And do you also think that he will use the GPU, CPU, motherboard, fans and storage maxed at the same time? How is even overclocking going to affect how much power the fans and storage uses?

Decent PSUs are rated for their full power 24/7 under their max temperature for the entirety of their warranty, so there is absolutely no issue running a PSU at 100% load for a few hours per day. 

What's that difference in efficiency, like 2%? At 400W load that is a difference of ~10W. So efficiency doesn't even matter

Edited December 21, 2017 by seon123
Something something

[1234vietnam]

13 minutes ago, seon123 said:

Do you seriously think that a motherboard, fans and storage will use 100W? Which, btw, according to your numbers is more than the CPU? And do you also think that he will use the GPU, CPU, motherboard, fans and storage maxed at the same time? How is even overclocking going to affect how much power the fans and storage uses?

Decent PSUs are rated for their full power 24/7 under their max temperature for the entirety of their warranty, so there is absolutely no issue running a PSU at 100% load for a few hours per day. 

What's that difference in efficiency, like 2%? At 400W load that is a difference of ~10W. So efficiency doesn't even matter

okay you're right. 

[Stefan Payne]

1 hour ago, Prqnk3d said:

( GPU TDP - 300W     +      CPU TDP - 95W      +     Motherboard/Storage/Fans - 100W )   *   1.5 To get overclocking headroom, not  put too much stress on the PSU and get better efficiency. 

Your calculation is totally wrong.

You need measurements. And also the times 1.5 is nonsense. Why would you do that?!

Modern PSU are rated for 24/7 use at 40 or 50°C and 100% load. There is absolutely no problem with that...

 

And other components besides CPU and GPU consume next to nothing. Nothing really worth talking about.

The 100W for 'the rest' would mean that some komponents would get seriously hot and need serious cooling with a really serious fan!

Something must be glowing hot to consume that much power...

 

You have to see what kind of heatsink you need for your 100W CPU to keep it cool or a ~100W TDP Graphics card. What else could come close to it?
The only thing there is that could consume some kind of power is the CPU VRM, but for that you can assume at least 85% efficiency!

And 85% efficiency at 100W load isn't even 20W. And modern Chipsets don't even come with heatsinks on OEM Boards for generations!!

The ones that are on modern ones are more for show than useful...

Only with an nForce 590 or similar you might possibly have a point...

 

Quote

As shown in the image, efficieny is best at 300W out of 750W. 

Yes, and?

We are talking about something like 2% difference between top and 100% load...

Is that really worth talking about?!

Here you see something different, German, can't be bothered to translate the description but should be obvious, I think.

 

Enermax MaxTytan im Test - Schönheit mit Titanium Effizienz  - Effizienz und Leistungsdaten (3/10) Enermax MaxTytan
Seasonic Focus+ 650W Gold, 30%
Corsair HX750W, 40% und schau dir mal an, wie flach die Effizienz "Kurve" auf 230VAC ist.
Das von dir verlinkte Pure Power ist auch bei 30% Last am Effizientesten
Cooler Master V550S, bei 20% am effizientesten!
Chieftec Proton 1000W, 30%
750W Proton, 30-40%
Chieftec Power Smart, 40%
1000W Leadex II, 30%

[STRMfrmXMN]

5 hours ago, Melodist said:

Hello there,

 

How much headroom you'd recommend for the 8700k and 1080ti / which power supply?

 

I've personally used an EVGA 850 for my 6900k and 1080ti build, what would you recommend?

8700K and 1080 Ti?

 

650W would be what I'd personally recommend if overclocking, a 650W EVGA G3, Corsair TXM/RMx/RMi, Seasonic Focus Plus, etc, would be fine.

[STRMfrmXMN]

2 hours ago, Prqnk3d said:

( GPU TDP - 300W     +      CPU TDP - 95W      +     Motherboard/Storage/Fans - 100W )   *   1.5 To get overclocking headroom, not  put too much stress on the PSU and get better efficiency. 

 

As shown in the image, efficieny is best at 300W out of 750W. 

 

That is, at best, a messy way to do that.

 

My 1700X and GTX 970 system, by your logic - 

 

145W TDP 970 - OC'd by +12 MV

95W TDP 1700X - OC'd to 3.8GHz at 1.3V  (Note, that I have a KillAWatt and have measured that, from my PSU, the system demands 330W, or about 370W at the wall)

+ 100 random watts that come from the sky??

 

* 1.5

 

So you're saying that my system would demand 510W. I'd pass on that weird math. You also note efficiency, a factor that shouldn't be given weight at all in this day and age, especially when power supplies have different "efficiency curves" than what people think to be standard.

 

 

[1234vietnam]

4 minutes ago, STRMfrmXMN said:

That is, at best, a messy way to do that.

 

My 1700X and GTX 970 system, by your logic - 

 

145W TDP 970 - OC'd by +12 MV

95W TDP 1700X - OC'd to 3.8GHz at 1.3V  (Note, that I have a KillAWatt and have measured that, from my PSU, the system demands 330W, or about 370W at the wall)

+ 100 random watts that come from the sky??

 

* 1.5

 

So you're saying that my system would demand 510W. I'd pass on that weird math. You also note efficiency, a factor that shouldn't be given weight at all in this day and age, especially when power supplies have different "efficiency curves" than what people think to be standard.

 

 

okay, i was wrong.

at least i learned stuff

[STRMfrmXMN]

9 minutes ago, Prqnk3d said:

okay, i was wrong.

at least i learned stuff

It's all good

 

If you ever wanna see how much power your PC uses then a KillAWatt is cheap and does decent for a cheap tool.

[Masada02]

My go-to is always to get a capacity that is at least double what you will realistically use and a PSU that can run fanless. That way you can run games at fanless operation on the PSU, and cut down on overall noise of your PC. But hey, I like my PCs to be quiet. If noise doesn't bother you, get the bare minimum and have that loud-ass PSU fan run all the time.

 

My system (not overclocked at all) peaks at around 420W at the wall depending on the game. 3DMark will push it over 500W. 

[STRMfrmXMN]

1 minute ago, Masada02 said:

My go-to is always to get a capacity that is at least double what you will realistically use and a PSU that can run fanless. That way you can run games at fanless operation on the PSU, and cut down on overall noise of your PC. But hey, I like my PCs to be quiet. If noise doesn't bother you, get the bare minimum and have that loud-ass PSU fan run all the time.

 

My system (not overclocked at all) peaks at around 420W at the wall depending on the game. 3DMark will push it over 500W. 

The fan will run depending on how hot the unit is, not how heavy the load on it is.

[Masada02]

1 minute ago, STRMfrmXMN said:

The fan will run depending on how hot the unit is, not how heavy the load on it is.

Depends on the PSU. The EVGA 1600T2 I had previously cycled the fan based on load percentage. In ECO mode it would stay off under 40%, anything more kicked it on.

[seon123]

3 minutes ago, Masada02 said:

My go-to is always to get a capacity that is at least double what you will realistically use and a PSU that can run fanless. That way you can run games at fanless operation on the PSU, and cut down on overall noise of your PC. But hey, I like my PCs to be quiet. If noise doesn't bother you, get the bare minimum and have that loud-ass PSU fan run all the time.

 

My system (not overclocked at all) peaks at around 420W at the wall depending on the game. 3DMark will push it over 500W. 

That's not how this works. For example, the EVGA G3 850W will produce 40dBA at a 425W load. The RM550x will produce 10dBA under a 440W load. Fans are controlled by temperature, not by load (in any decent PSU).

Even the low end Pure Power 10 500W produces 24dBA under a 450W load. That's quiet. 

Was the power draw measured at the wall? Assuming 90% efficiency, that's a 450W load on the PSU.

 

Numbers from Cybenetics

[Masada02]

1 minute ago, seon123 said:

That's not how this works. For example, the EVGA G3 850W will produce 40dBA at a 425W load. The RM550x will produce 10dBA under a 440W load. Fans are controlled by temperature, not by load (in any decent PSU).

Even the low end Pure Power 10 500W produces 24dBA under a 450W load. That's quiet. 

Was the power draw measured at the wall? Assuming 90% efficiency, that's a 450W load on the PSU.

 

Numbers from Cybenetics

It works both ways. In EVGA's PSUs the fan will kick on based on load and/or temperature, not just one or the other. Even if temps are in check if you cross the load threshold the fan will kick on. 

 

If you want to get into real numbers you might as well use 94% efficiency for my PSU. But even then we are talking fully stock clocks and voltages (and technically my 1080Ti is at 70% power target, though that doesn't matter in almost every game).

 

My point still stands: to have a silent pc you need need a big PSU to run fanless at almost all times.

[seon123]

3 minutes ago, Masada02 said:

It works both ways. In EVGA's PSUs the fan will kick on based on load and/or temperature, not just one or the other. Even if temps are in check if you cross the load threshold the fan will kick on. 

 

If you want to get into real numbers you might as well use 94% efficiency for my PSU. But even then we are talking fully stock clocks and voltages (and technically my 1080Ti is at 70% power target, though that doesn't matter in almost every game).

 

My point still stands: to have a silent pc you need need a big PSU to run fanless at almost all times.

The fan is controlled by the internal temperature, which will increase with an increased load. So it's still temperature controlled. 

In Anandtech's review of the 1080 Ti FE, the system drew about 400W at the wall with an AX1200i and an overclocked 4960X under Furmark and Crysis 3. So I seriously doubt that your PC would use over 100W more than that. 

 

So you're telling me that you're going to hear a 10dBA PSU fan even with the CPU and GPU fans under a heavy load? Somehow?

 

I already came with an example that showed that a higher capacity PSU can be noisier than a lower wattage PSU. There is no good generalisation; a quiet PSU will be quieter than a noisy PSU, regardless of the max wattage.

Go to Cybenetics' website, you'll find lots of quiet low wattage PSUs, and lots of louder higher wattage PSUs. 

[STRMfrmXMN]

10 minutes ago, Masada02 said:

It works both ways. In EVGA's PSUs the fan will kick on based on load and/or temperature, not just one or the other. Even if temps are in check if you cross the load threshold the fan will kick on. 

You ever heard the phrase "correlation does not imply causation?" That's what you're doing here. It's incorrect, but I see what you're doing wrong.

 

I would imagine you're looking at a chart like this.

 

You would assume, then, that the PSU's fan kicks on as the load goes up, and that's not inherently untrue as the PSU does produce more heat as the unit is stressed more, but if you were to put the PSU in a subzero room and load it up to 1600W, because the PSU is sitting cozily at maybe 2 or 3 degrees Celcius, the fan won't come on. So, as I said, it's a thermal probe that sends a PWM signal to the fan that's dependent on what the probe reads. The PSU could be getting stuffed with carpet while the system is idling and the fan will start screaming.