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Can I run 3 x 7950 cards on 850w

Catanonia

Catanonia

Catanonia

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Is this possible.

3 x Sapphire HD7950 cards on a 850 Corsair Power Supply.

PC will be a 3930K water cooled, 32GB Ram, SSD

Now the CPU will be idle, monitors off, but the graphics cards will be running full pelt with stock fans for 24/7 Case will be open to cold air from open window. (Bitcoin mining)

Is this possible on a 850w supply ?

Thanks

Cat
 
it is, but a bit of a waste of time at the moment as crossfire doesn't give you better results than a single card;

sleepingdogs1920x1080pl.png


http://www.pcper.com/reviews/Graphics-Cards/Frame-Rating-GeForce-GTX-660-Ti-and-Radeon-HD-7950
 
@stock the 7950s are pretty low power, trifire with a normal CPU loads at around 600W. With a gonna assume, overclocked hexcore and mild oc on the cards? you'll be pushing 800-850w. Still well within spec of an 850w Corsair unit.
 
Admittedly I am not at all in the loop with BitCoin Mining, but since it runs on GPUs, wouldn't a healthy overclock on the three GPUs help improve his mining? This could push the output from 600W into the 750-800W area.

Also, if the PSU is going to be running full pelt 24/7 for weeks or months, wouldn't it make sense to step up to the 1000W so the PSU isn't running near 100% capacity all the time?
 
ArchAndroid said:
Admittedly I am not at all in the loop with BitCoin Mining, but since it runs on GPUs, wouldn't a healthy overclock on the three GPUs help improve his mining? This could push the output from 600W into the 750-800W area.

Also, if the PSU is going to be running full pelt 24/7 for weeks or months, wouldn't it make sense to step up to the 1000W so the PSU isn't running near 100% capacity all the time?
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7950 at stock speed will use under 150w. Assuming his power supply has 6 pci-e connectors it should be perfectly fine especially since his cpu will be doing nothing.
 
As most "quality" psu's like corsair can run above their rated spec I wouldn't see a problem.
 
Does overclocking really help much with bitcoin mining?

I been trying mining for first time today and the overclocking the 7950 gives me less than 10% increase and makes my temps go up really high.

running mine at 1050mhz and 1.2v gives me temps of 63c and a hashrate of 500. If I try and push any more out of it temps go into the 70's and hasrate only go's up very little.

What should I be aiming for?
 
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Havana_UK said:
If you're only BitCoin mining, why not just buy a dedicated BitCoin miner box?

http://www.butterflylabs.com/landing/landing-aw.php
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I only started bit coin mining today but it seems that people are having lots of trouble getting hold of them asics you linked to.

People preordered them last summer and are still waiting :eek:

By the time you get the box there might not be any bit coins left lol
 
£70 a week (using 3 7950 without taking into account electricity cost) is a waste of time? At the current prices its well worth doing for a bit of extra pocket change :P
 
andybird123 said:
it is, but a bit of a waste of time at the moment as crossfire doesn't give you better results than a single card;

sleepingdogs1920x1080pl.png


http://www.pcper.com/reviews/Graphics-Cards/Frame-Rating-GeForce-GTX-660-Ti-and-Radeon-HD-7950
Click to expand...

And don't put all CF into the same basket, Tri Fire can have significant difference in behaviour and there is also the use of Vsync and Capping.

30ms is mostly not perceivable but the issue there is on the CF it fluctuates from 30-0-30-0 which could make it more perceivable.
 
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arc@css said:
Is it still worth doing (I know practically nothing about bitcoining)?
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It was much more worthwhile in the early stage, but now with the return hugely decreased (due to too many miners) vs electricity cost considered, not really sure it really is still worth the bother anymore...and that's not even include the consideration of shorten of lifespan for the cards (i.e. if the card(s) die on you).
 
Drangueos said:
don't believe on everything that you see on the internet...
Click to expand...

Andy's on a colossal biblical crusade against AMD at the moment, pedantically posting in almost every other thread, the hate is that bad he's even stooping as low as fabricating thread titles.:o

He keeps forgetting that Nvidia can't eradicate the stutter problem in single card mode though never mind dual cards.:eek:

I too have the stutter bug / micro stutter again with these new drivers
Click to expand...

Funny that Nvidia think that people need to analyse frame rates differently, when I still get (occasionally) the stutter bug with the latest drivers in BF3.
Click to expand...

Drangueos said:
I'm running crossfire and I see a huge difference between one and two cards, I'm not talking about FPS showing with programs.. I'm talking about what my eyes can see.
Click to expand...

+1

I use 120Hz FS 3D, one card-choppy and unplayable at desired settings, two cards-smooth and playable.

It's not without it's problems though, it's game dependant at the moment but hopefully AMD will sort it all out and put it to bed.
 
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