How much more power does radeon 79xx need when overclocked? Im buying psu quick

Solution
Using the MSI Radeon HD 7970 Lightning (i.e. non-reference design card) as an example:

Peak Card Power during Gaming

Factory Core Clock: 1070 MHz, Factory Memory Clock: 1400 MHz : 224.97 Watts

OC Core Clock: 1170 MHz, OC Memory Clock: 1600 MHz : 246.51 Watts (an increase of 21.54 Watts over factory clocks)

OC with GPU Vcore increased to 1.3V & Core Clock: 1250 MHz, OC Memory Clock: 1600 MHz : 336.97 Watts (an increase of 112 Watts over factory clocks)

For a system using a single AMD Reference Design Radeon HD 7970 graphics card AMD specifies a minimum of a 500 Watt or greater system power supply. The power supply should also have a maximum combined +12 Volt continuous current rating of 40 Amps...
Using the MSI Radeon HD 7970 Lightning (i.e. non-reference design card) as an example:

Peak Card Power during Gaming

Factory Core Clock: 1070 MHz, Factory Memory Clock: 1400 MHz : 224.97 Watts

OC Core Clock: 1170 MHz, OC Memory Clock: 1600 MHz : 246.51 Watts (an increase of 21.54 Watts over factory clocks)

OC with GPU Vcore increased to 1.3V & Core Clock: 1250 MHz, OC Memory Clock: 1600 MHz : 336.97 Watts (an increase of 112 Watts over factory clocks)

For a system using a single AMD Reference Design Radeon HD 7970 graphics card AMD specifies a minimum of a 500 Watt or greater system power supply. The power supply should also have a maximum combined +12 Volt continuous current rating of 40 Amps or greater and have at least one 6-pin and one 8-pin PCI Express supplementary power connectors.

For a system using two AMD Reference Design Radeon HD 7970 graphics cards in 2-way CrossFireX mode AMD specifies a minimum of an 850 Watt or greater system power supply. The power supply should also have a maximum combined +12 Volt continuous current rating of 59 Amps or greater and have at least two 6-pin and two 8-pin PCI Express supplementary power connectors.

Total Power Supply Wattage is NOT the crucial factor in power supply selection!!! Sufficient Total Combined Continuous Power/Current Available on the +12V Rail(s) is the most critical factor.

Overclocking of the CPU and/or GPU(s) may require an additional increase to the maximum combined +12 Volt continuous current ratings, recommended above, to meet the increase in power required for the overclock. The additional amount required will depend on the magnitude of the overclock being attempted.
 
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this is very interesting just increasin core by 80 from 1170 and voltage to 1.3v add 112 watts.

Is there a way to calculate what watts will my card have when i overclock it to some values?
 


Not all Radeon HD 7970 will behave the same way when overclocking. Using the correct measuring instruments and techniques is the only way.

Only some of the non-reference design Radeon HD 7970 cards allow you to modify the GPU voltage. The manufacturers of those cards will advertise that feature.
 

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oh i just found this "Digital chips are CMOS, and CMOS power consumption pretty much goes up with frequency. IOW if a stock 4 GHz CPU consumes 100W, overclocking it to 5 GHz makes it consume 125W, assuming the voltage isn't changed. Power consumption goes up roughly with the square of voltage."

source: overclock.net/t/1413907/how-much-does-overclocking-increase-power-draw

is this true?
also video cards have different core and memory and shader mhz and voltage.What would be the difference be for each of them?
 


It's linear up to a certain point and begins to increase exponentially for some cards:
5850_plines.png



It can also be more linear like this card:
275_plines.png
 


On those cards that allow you to manually control the GPU voltage the power increase needed to achieve a higher clock speed will eventually become exponential.

Most graphics card manufactures will place temperature and power limits in the video BIOS to prevent it.
 

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because i will only gpu mine scryptcoins for profit i just wanna know the best overclock per watt amount.

So how can I measure gpu power usage cheaply and accurately?
(Ive read that those plug-in power meters are inaccurate)
 
Bitmining consumes a lot more power than gaming.

Take the AMD Reference Design Radeon R9 280X for example (i.e. it's fundamentally identical to the Radeon HD 7970 GHz Edition):

At factory clocks:

Peak power reached during gaming: 207 Watts

GPGPU (Bitmining): 257 Watts <=== that's 50 Watts more than when the card is used for gaming

That's going to generate a lot of heat inside of a computer case that you would need to get rid of too.

Define accurate. If you want laboratory grade calibrated accuracy that will cost you way more than you would want to spend.
 

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accurate enough for a low enough price.
What do You recommend?
 

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Thank You very much again.

are these accuracies true?
Ive read reviews of some like these and tehy said that two of the same meters would have a huge difference between the same thing
 


These devices are only used to give a good idea of what the power consumption is.

If you don't have the test equipment to determine the accuracy of these meters it's not going to matter much because you won't know if it's accurate or inaccurate.

At low power consumption those meters tend to be less accurate.
 

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I have two more questions:

can anything except temperature and voltage degrade gpu?

(I have 377 usd to spend on radeon for gpu mining and a psu.I will probably buy psu from europe and gpu from USA)

Most cheap psu brands are less known
is there any way to determine psu quality if no one has ever bought it?

 


If a PSU puts out high levels of ripple on its outputs it will eventually destroy the electrolytic capacitors on the graphics card, motherboard, hard disk controller circuit board, etc. That's why power quality is extremely important.

Knowing the OEM and its OEM platform of the PSU is a way to determine its quality. Seasonic is considered to be one of the best. Seasonic has its own retail models under the Seasonic name. All of XFX's PSU models are made by Seasonic. Most of Antec's High Current Gamer models, all of the True Power Classic and True Power New models, some of the Neo Eco models are made by Seasonic. All of the currently available (i.e. not discontinued) Corsair AX models are made by Seasonic. The Cooler Master V Series are made by Seasonic.
 

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This is very surprising.What changes do these companies implement to original psu?

I just searched for the psu brand oem and no results.What else can I do?
 


Some of the OEMs will allow the quality of the electrolytic capacitors to be changed (i.e. lower or higher quality depending on the target market) or the use of a different cooling fan, maybe modular output cables and of course a different shell and paint color scheme.

You can use the PSU Review Database here: http://www.realhardtechx.com/index_archivos/Page541.htm
 

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thank you very much again ur really helpful :D This lists almost all psu reviews i couldnt find!