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Crossfire 7970's and power question

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#1
Would my current PSU sustain 2 7970's in CF?

Soz for small thread... But I must know
 

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#2
Easily. If you look at a review for the cards you'll see that they draw around 220 watts of power at most.
 
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#5
Off topic, your specs say your 2600k is stock? why haven't you overclocked it if so? I wouldn't recommend crossfire unless you are overclocking to at least 4GHZ+
 

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#6
with sandybridge chips overclocking dosent do a whole lot for performance unless CPU bottlenecked good examples would be Skyrim before the 1.4 patch,

otherwise the difference is around 5-7 fps gain on average going from 3ghz to 4.4 ghz

with crossfire memory bandwidth will do more for performance then core clock.

and yes the 1000w strider shouldnt have any trouble
 
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#7
Off topic, your specs say your 2600k is stock? why haven't you overclocked it if so? I wouldn't recommend crossfire unless you are overclocking to at least 4GHZ+
with sandybridge chips overclocking dosent do a whole lot for performance unless CPU bottlenecked good examples would be Skyrim before the 1.4 patch,

otherwise the difference is around 5-7 fps gain on average going from 3ghz to 4.4 ghz

with crossfire memory bandwidth will do more for performance then core clock.

and yes the 1000w strider shouldnt have any trouble
It's just a 2600... Not a 2600k
 

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#8
2600 can still clock past 4ghz

point is it wont matter a whole lot

the only real advantage from clocking your cpu would be that as you push an Sandybridge CPU's clock speed it also increases memory performance

example 1866 9 10 9 27 at 3.3ghz i get around 22GB/s bandwidth 1866 9 10 9 27 at 4.4ghz I get 24GB/s

something to keep in mind, for crossfire system bandwidth is pretty much critical with high end gpus.

but considering your on 2133 you should be just peachy performance wise.
 
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#9
And how do I clock it to 4GHZ?
 
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#10
Yer mate your power supply gunna b ample! No sweat.
 

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#11
turbo,

you can still set the turbo multi higher on P67 / Z68 if i remember right its a maximum of 8 multis from stock

so 3.4 + 4 = 3.8 +4 = 4.2ghz

so in theory you should be able to push the turbo multi up to 42x and get to 4.2ghz

you can also still overclock via BCLK, try 103 then 105 BCLK test for stability

at 103 x 42 = 4.3ghz
at 105 x 42 = 4.4ghz

so with a good chip you can still get past 4ghz. even on a 2600 non K
 
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#12
turbo,

you can still set the turbo multi higher on P67 / Z68 if i remember right its a maximum of 8 multis from stock

so 3.4 + 4 = 3.8 +4 = 4.2ghz

so in theory you should be able to push the turbo multi up to 42x and get to 4.2ghz
Sick will test this after WoW raid :p
 

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#13
http://www.bit-tech.net/hardware/cpus/2011/01/03/intel-sandy-bridge-review/5

depending on where you look it would be 3.8ghz max on 4 cores

at 105 BCLK on 38 multi would be 3990 core clock or 4ghz,

if you push turbo higher. you can get 4.1 single core 4.0 dual core 3.9 tri core and 3.8 quad

with BCLK you can push it to

1 core = 4300mhz
2 core = 4200mhz
3 core = 4095mhz
4 core = 3990mhz
 
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#14
Another question. Is it worth waiting for the price drops? Like, will they be big or small when the 6XX comes out?
 

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#15
Another question. Is it worth waiting for the price drops? Like, will they be big or small when the 6XX comes out?
How long is a bit of string?

If recent graphic card pricing is anything to go by then unless your idea of an acceptable wait is around 12-18 months, then any price drops are usually small change.
 
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#16
So... Dont bother waiting?
 
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#17
That is what I'm thinking "/
 

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#18
So... Dont bother waiting?
Well....

....I dont know how that price (the one u linked to) is in Australia, but providing it translates pretty close to $550 USD (taking tax into consideration of course), then if you really want to buy the card, dont wait, just buy the card.

If on the otherhand that price is grossly inflated over the RRP set by AMD, then wait until the mania dies down and/or supply matches demand. In the UK on the release day of the 7970, many retailers jacked the price of reference 7970 cards to £530+ and people still bought them cos the e/tailers who were selling at the £460 mark all sold out super fast (I got mine for £430 delivered).
 

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#19
I've got two Sapphire 7970's in CF. Earlier this week I burnt out my 750W thermaltake while mining. Got my 1000W last night... seems to running pretty great.
 
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#20
Picked up 2 Gigabyte Factory Overclocked 7970's.

Fkn expensive, but worth it!
 
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#21
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#22
you running just a single 1080p monitor?
2 monitors at the moment. Sometimes eyefinity when my bro isn't using his screen :p
 

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#23
Going from 6870's in CrossFire, all you need is a single 7970. Hopefully you don't run into any CrossFire hassles.
 
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#24
Going from 6870's in CrossFire, all you need is a single 7970. Hopefully you don't run into any CrossFire hassles.
It's massive overkill. But I'd rather have excess FPS then not enough....

 
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#25
I dunno, you probably won't get much more performance if you don't overclock your CPU more than 4ghz for crossfire. I remember doing a crossfire bench for GPU in 3D Mark Vantage and I remember from my 6950 crossfire setup that my score started dropping by a good margin when I clocked my 2600k below 4.2ghz.

So basically you'll be a fat guy running in really good running shoes, if you wanna make the most of your nice pair of shoes you'd need to OC and slim down! :laugh:

Not to mention you'll get great FPS gains in WoW raids and towns.