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I am upgrading to watercooled quadfire 7970s with a 3770k. The CPU will be running at 4.5GHz and the GPUs OCed to at least 1250/1500 (I know they can do it). I have a 1200AX and wanted to make sure that it would support a watercooled system like this. Looking at the PSU calcs I think I should be safe but I wanted to be sure with the PSU gurus here at ocn.

Thanks.
 

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Quote:
Originally Posted by TinDaDragon View Post

Plenty
Nope.
smile.gif


@OP, highly overclocked 7970s are power pigs, I would suggest upgrading to a higher output unit.
 

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Quote:
Originally Posted by Original Sin View Post

Nope.
smile.gif


@OP, highly overclocked 7970s are power pigs, I would suggest upgrading to a higher output unit.
Aye, those things are more than insane. I've seen a single 7970 draw 600 watts by itself under an LN2 run....

The ARES II draws 950 watts ALONE in QuadFire. That's not counting the rest of the system OR overclocking. Max OC on water or air 7970's.... they're singlehandedly keeping the 1200+ watt PSU market alive.
 

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Not even for gaming will that psu do the job and for benching you would need a LOT more.

Here is the most I have drawn from the wall with my 3x watercooled 7970's to date.

http://www.stewartsanderson.com/p511390059/e5528802a

Multiply that by 0.80 and you will have a figure for a PSU to do that at 80% efficiency. Then add another 400w for your 4th card and a bit more to keep it within sensible limits away from max output.

Ideally, run 2x PSU's.
smile.gif
 

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Quote:
Originally Posted by Stu-Crossfire View Post

Not even for gaming will that psu do the job and for benching you would need a LOT more.

Here is the most I have drawn from the wall with my 3x watercooled 7970's to date.

Multiply that by 0.80 and you will have a figure for a PSU to do that at 80% efficiency. Then add another 400w for your 4th card and a bit more to keep it within sensible limits away from max output.

Ideally, run 2x PSU's.
smile.gif
No, no and no.
No 400W addition (why would he do that?), no senseless multiplication (why 0.8 when your PSU is clearly 0.88-0.9 @ 230V) and no 2 PSU setup (that's never Ideal).
 

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H
Quote:
Originally Posted by Original Sin View Post

No, no and no.
No 400W addition (why would he do that?), no senseless multiplication (why 0.8 when your PSU is clearly 0.88-0.9 @ 230V) and no 2 PSU setup (that's never Ideal).
Good evening to you too.
smile.gif

Instead of talking me down. Why don't you point out what's wrong with my reply so that you can help him out instead of trying to make me look silly.

To answer your questions though, as it WILL help him understand my thinking...

Why did I add another 400w to my figures?
Because overclocked my GPU draws about 400w and I only have three. He wants FOUR.

Why 0.8? I made it clear that figure would give him the power draw on an 80% efficient PSU. If he buys a 90% efficient PSU he will have valuable headroom. You never know, he may want to run 15 USB 3 devices on this rig? They all take additional power that I haven't taken into account with my reading.

Why are 2 PSU'S not going to be ok? Which one PSU is going to do the job for him? If there are ANY his choices will be VERY limited. Or he can have a pick of a LOT of 1kw exceptional units and buy 2 of them. Why is that such a bad idea?

I look forward to seeing why my reply was so wrong, always willing to learn.
smile.gif
 

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I'm not "talking you down" Stu, we've been through this in your thread, for hours on end.. and you got what you wanted from that, so I exited that discussion for reasons that have to do with the idiocy and frustration of self repetition. Sorry, but I'm not gonna' do that again here (don't have the time, nor the patience for it), all the info you're looking for is already in that thread, read it again and think about it.
However, I am pleasantly surprised by the fact that you held on to the PSU, which gives the impression that you got it (to an extent).
 

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There's a user here that has an i7-3970k @ 4.8GHz and quad-fire 7970 overclocked on the G1600 that Jagz recommended, so it would power that 3770k setup and show that you don't need a second PSU.
 

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Well, I have given my opinion and backed it up with my own power readings from my own trifire 7970 rig.
I don't know what else I can do to be honest. I hope the OP gets sorted.
smile.gif
 
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