underclocked pc wattage? all psu calcs results are very different

d359233drdrbcom

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Jan 26, 2014
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After using all psu calcs and getting very different results i hope you will be more accurate.Even AMD recommendation is overestimated because it tells you watts according to their opinion on what most people have in their pc and a big safety margin

H81 Pro Btc
G1820
Goodram ddr3 1333 MHz 9/9/9/24 2gb
DT100G3/16GB pendrive for OS
radeon 7950 or newer

no sound card hard drive and whatever.After setup ill unplug keyboard mouse monitor whatever else even usb after os copied to ram for max power saving.Everything underclocked as much as possible except overclocked radeon for gpu mining.

Can you estinate how many watts power supply i really need?
 
PSU is more about quality than watts. If you stick with SeaSonic or XFX, you can do just fine with a single GPU system with 450w+

As reference, my overclocked and overvolted i5-4670k and 760 HAWK only draw a max of 350w at full 100% load in Prime 95 running alongside Unigine Heaven.
 
If you're going to be mining, getting a higher 80+ rating may be beneficial. But if you compare a 300w PSU to a 500w PSU, the PSU will only draw what it needs from the wall, so a 500w PSU won't draw any more power than a 300w, save for slight variations due to efficiency.

Seasonic has a great 350w PSU that would do great for what you're looking at.
 

d359233drdrbcom

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thanks but how many watts will this rig take ithout radeon and with radeon?
i might buy psu with enough watts for two radeon but i need to know how many watts at least i should look on.

watts increase less than price in psu.So there is a price point about in which it is better to buy another psu than have one bigger.
 

d359233drdrbcom

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is this with all the underclocking taken into account?
also mining tdp is much higher than in gaming
 

jb6684

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You can't use two (2) power supplies (won't fit in a case, and, doesn't work electrically...)

You need enough power to support Peak demand, not "just enough" or else your system will crash..

If you want to save energy usage, get the most efficient power supply you can, Gold or Platinum energy certification at least. (NOTE: most supplies under 450watts are cheap units with low, low efficiency to save money on build cost, not energy usage...)
 


It doesn't matter what you're doing with the card, a card at 100% use will draw the same amount of power. Whether that's playing Hello Kitty at 4k, or mining, a 150w card will only draw 150w, unless you tweak it to pull more.

And yes, you won't honestly save enough power by underclocking to drop down a step in PSU size.
 


If what you said is true then these two graphs should be exactly the same:

04-Power-Consumtion-Gaming.png
05-Power-Consumtion-Torture.png
 

d359233drdrbcom

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Why is Thermal Desgin Power confused as max power?
Thermal Design Power is amount of Heat in Watts generated as Waste from actual whole power usage.It is called Thermal Design Power because it is a value in Watts of cooling Power which a Thermal Design is based on.


cpu-world.com
The Thermal Design Power (TDP) is the average maximum power a processor can dissipate while running commercially available software. TDP is primarily used as a guideline for manufacturers of thermal solutions (heatsinks/fans, etc) which tells them how much heat their solution should dissipate. TDP is not the maximum power the CPU may generate - there may be periods of time when the CPU dissipates more power than designed, in which case either the CPU temperature will rise closer to the maximum, or special CPU circuitry will activate and add idle cycles or reduce CPU frequency with the intent of reducing the amount of generated power.

So TDP is a value of Watts but as Heat not whole power usage =Work + Waste (Heat)



How to find out max power not tdp of radeon?