Is my PSU sufficient?

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Loxosceles19

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So I have overclocked my 6850k to 4.25ghz at 1.26V and I run my 1080 at max power power 2000mhz OC. I have a 650watt 80+ gold Rosewill Capstone. Is my PSU sufficient, or do I need to replace:

https://pcpartpicker.com/list/3y88m8

I have carried it over from a previous, non-broadwell-e build. I'm worried it might be close to insufficient, as I max out my rig when gaming and streaming. I also maxed out my budget, but could eat rice and beans for a couple weeks if a PSU upgrade is necessary. Thanks!
 
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Wrong section, this is the Overclocking & Cooling section.

Knowing what PSU you currently have would be extremely useful information.
 
Loxosceles19 said:
So I have overclocked my 6850k to 4.25ghz at 1.26V and I run my 1080 at max power power 2000mhz OC. I have a 650watt 80+ gold Rosewill Capstone. Is my PSU sufficient, or do I need to replace:

https://pcpartpicker.com/list/3y88m8

I have carried it over from a previous, non-broadwell-e build. I'm worried it might be close to insufficient, as I max out my rig when gaming and streaming. I also maxed out my budget, but could eat rice and beans for a couple weeks if a PSU upgrade is necessary. Thanks!
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Should be fine, provided it hasn't lost too much capacity with age. (no way of actually telling that)

FYI: My desktop (6600k, overclocked to 4.3Ghz and a GTX970, 2x SSD) only sucks down like ~250W max at the wall and that's with everything artificially loaded down to 100%.
Almost forgot to mention: what's feeding all of that? a 450W PSU. Hasn't been an issue yet.
 
FnordMan said:
Should be fine, provided it hasn't lost too much capacity with age. (no way of actually telling that)

FYI: My desktop (6600k, overclocked to 4.3Ghz and a GTX970, 2x SSD) only sucks down like ~250W max at the wall and that's with everything artificially loaded down to 100%.
Almost forgot to mention: what's feeding all of that? a 450W PSU. Hasn't been an issue yet.
Click to expand...

Wow, that's good to know! Why does everyone seem to build with 400+ watts over the TDP rating for their builds? Just for peace of mind? Or good marketing?
 
Loxosceles19 said:
Wow, that's good to know! Why does everyone seem to build with 400+ watts over the TDP rating for their builds? Just for peace of mind? Or good marketing?
Click to expand...
All of the above really. That and rather inaccurate "PSU calculators". The one from coolermaster is too high by a good 30%. (or more)
 
pendragon1 said:
yup, piece of mind or epeen.
Click to expand...
Also loss of efficiency over time, other features (modular cables, USB monitoring, etc), and rail configurations that make it hard to get the full output out of it.

For instance, I have a very unique "700 watt" PSU in one of my airborne systems, but it supplies like 300+ watts of that on the 5v rail, which isn't terribly useful these days. That particular PSU is an oddbal in that the supply to it is 24VDC from the aircraft, and not AC wall power, but it still illustrates the point that the output number does not tell the full story of how capable that PSU will be for a given system.
 
RazorWind said:
Also loss of efficiency over time, other features (modular cables, USB monitoring, etc), and rail configurations that make it hard to get the full output out of it.

For instance, I have a very unique "700 watt" PSU in one of my airborne systems, but it supplies like 300+ watts of that on the 5v rail, which isn't terribly useful these days. That particular PSU is an oddbal in that the supply to it is 24VDC from the aircraft, and not AC wall power, but it still illustrates the point that the output number does not tell the full story of how capable that PSU will be for a given system.
Click to expand...

Loss in efficiency has nothing to do with it. Capacitors degrade over time, leading to worse power quality, but that takes a very long time in modern PSUs to have a detrimental effect. Features are spread across the entire power lineup, not just limited to high power ones. Modern PSUs all have proper rail configurations for any system that is not a server with tons of hard drives.

None of the reasons you listed are valid reasons for modern PSUs. And by modern, I mean anything newer than 2010, and even many PSUs before then.
 
I go overkill for piece of mind. Plus, i tend to tinker a LOT so i don't know when i'll have a Trifire setup once more :p
 
I prefer to look up the power efficiency curve of the power supply I'm looking at buying vs the actual draw of the system I'm using with it.
For example, my current system draws around 350w at load. I used an EVGA 850 B2 Gold PSU that is around 85% efficient at this range.
You should figure out the power draw of your setup and then find the efficiency curve for the supplies you're considering, and try to match the max efficiency to the actual power draw.
Here's an example of what the chart for mine looks like.
f1.jpg

You'll see that the efficiency curve starts topping out around the 450-500w range.
Every PSU is different, so just saying "your system only draws 300w at full load, so you only need a 400w" is just wrong.
 
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GhengisKhan said:
I prefer to look up the power efficiency curve of the power supply I'm looking at buying vs the actual draw of the system I'm using with it.
For example, my current system draws around 350w at load. I used an EVGA 850 B2 Gold PSU that is around 85% efficient at this range.
You should figure out the power draw of your setup and then find the efficiency curve for the supplies you're considering, and try to match the max efficiency to the actual power draw.
Here's an example of what the chart for mine looks like.
View attachment 19816
You'll see that the efficiency curve starts topping out around the 450-500w range.
Every PSU is different, so just saying "your system only draws 300w at full load, so you only need a 400w" is just wrong.
Click to expand...

/facepalm

Seriously. Just stop. Really. Stop. Your "advice" crosses the border from helpful to harmful.

You need to read this article from a true power supply expert: http://www.overclock.net/t/872013/50-load-myth
 
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