550W PSU sufficient for 2500k @ 4.1 + 7970 OC'd?

Freddy1765

Senior member
May 3, 2011
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I'm close to taking the plunge on a new GPU, but keep debating with myself whether I should go 670, 7950 or 7970.. One thing holding me back from the 7970 is the power consumption, as I'm unsure whether my 550W can handle it with an overclock along with my 2500K (4.1 GHz).
My PSU is rated at 17 amps on each of its two 12v rails, equaling 408W on the 12V.. Is this sufficient for running this system?

I won't be tampering with the voltage on the GPU, only clocks.
 

Freddy1765

Senior member
May 3, 2011
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I've got this one:
http://www.anandtech.com/show/2724/2

Although I'm now debating whether to get a 7950 instead, simply because it's so much cheaper and seems to overclock and perform just as well. I assume it'll be safer to OC on my current PSU as well, and I'd really hate to spend ~$70 more on a 7970 + $70 on a PSU to run it..
 

Freddy1765

Senior member
May 3, 2011
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I've ordered the Gigabyte 7950 :)
For 1080 it seems the most logical choice, especially given the higher memory bandwidth and VRAM compared to nVidia's 670. I hope it's the right decision, but only time will tell!
 

lehtv

Elite Member
Dec 8, 2010
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The VRAM is of no consequence for 1080p. Neither is the memory bandwidth, really. Performance per dollar, the 7950 and 660 Ti are pretty much equal, while the 670 costs more than it's worth (as does the 7970). But it's the overclockability of the 7950 that puts it well ahead of 660 Ti in terms of value. At 1.1GHz it will rival a stock GTX 680.

The Gigabyte model usually overclocks well and handles overvolting well.
 
Nov 26, 2005
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It may be ok depending on the games you play. If they don't tax the GPU as much then I think you'd be ok, but games like Crysis and other highly GPU driven games will push that PSU close to the limit. Just be careful
 

Freddy1765

Senior member
May 3, 2011
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Should I be genuinely concerned about my PSU? I've done some reading, and it seems to be perfectly safe increasing volts to achieve higher core clocks, and doing so does sound tempting. The money I "saved" by going 7950 over 670 means I could invest in a new PSU if it's really necessary.
 

Necc

Senior member
Feb 15, 2011
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Total system power consumption with 7950 Playing metro 2033 (which is a highly GPU driven game ) is 353W and thats using an intel Core i7-3960X @ 4.3GHz.

So you're absolutly fine with your 550W PSU (which btw is made by seasonic)
 

aaksheytalwar

Diamond Member
Feb 17, 2012
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Wont be okay. Even if you connect just the 7950 to one of the 12va lines, 17A is less than what it uses at max even at stock.

Buy a quality 650 watts.
 

lehtv

Elite Member
Dec 8, 2010
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Wont be okay. Even if you connect just the 7950 to one of the 12va lines, 17A is less than what it uses at max even at stock.

17A * 12V = 204W
7950 @stock = 154W (peak wattage in Crysis 2). Even the wattage in Furmark burn test is only 175W.

So no, 17A isn't less than what it uses.

Buy a quality 650 watts.
Whoa there. Just because the OP's unit is somewhat weak for a 500W unit doesn't mean he needs a 650W unit. A good quality 500W-550W unit with +12V rated near the total wattage will be fine.
 

Necc

Senior member
Feb 15, 2011
232
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Whoa there. Just because the OP's unit is somewhat weak for a 500W unit doesn't mean he needs a 650W unit. A good quality 500W-550W unit with +12V rated near the total wattage will be fine.

Agreed.
 
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