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Other => CPU/GPU Bitcoin mining hardware => Topic started by: Kinetic915 on May 20, 2013, 04:55:30 PM



Title: will 1200 watts run it?
Post by: Kinetic915 on May 20, 2013, 04:55:30 PM
Hello all,

Just getting some opinions.  would a 1200w psu run 1 7970, 3 7950s, 1 ssd, 1 hard drive, 1 i7 3770k, and related peripherals?

thanks!


Title: Re: will 1200 watts run it?
Post by: bowen151 on May 20, 2013, 05:02:46 PM
The TDP of a 7950 is around 200W I believe and the TDP of the 7970 is closer to 250W, so your PSU should be able to handle the remaining devices without any problems.

2 hard drives and a 3770k in there is a bit much IMO though


Title: Re: will 1200 watts run it?
Post by: Kinetic915 on May 20, 2013, 06:29:57 PM
The TDP of a 7950 is around 200W I believe and the TDP of the 7970 is closer to 250W, so your PSU should be able to handle the remaining devices without any problems.

2 hard drives and a 3770k in there is a bit much IMO though

gotcha thanks for the response!


Title: Re: will 1200 watts run it?
Post by: grobbes on May 21, 2013, 01:51:07 AM
If voltage unlocked, you can usually drop about 50-60 watts a card. I run 4 7950s, dual core celeron, and raptor HD with room to spare. It's more important to get Gold level or above


Title: Re: will 1200 watts run it?
Post by: notaek on May 21, 2013, 01:53:20 AM
You should be able to do it with no issues at all.  Is this solely a mining rig or will you be using it for other stuff too? 


Title: Re: will 1200 watts run it?
Post by: Kluge on May 21, 2013, 02:01:53 AM
Hello all,

Just getting some opinions.  would a 1200w psu run 1 7970, 3 7950s, 1 ssd, 1 hard drive, 1 i7 3770k, and related peripherals?

thanks!
(250+(200*3)+15+25+77)*1.2=1160.4W PSU required. "*1.2" accounts for components possibly going over TDP, and peripherals. It will *probably* work, so long as you don't OC. PSU DC output decreases significantly below specs when running hot, generally (however, PSUs are generally able to output significantly higher wattage under ideal conditions than it's rated for). Considering it's going full-throttle... no guarantees if the ambient temperature isn't fairly cool. I'm not sure if I'm remembering this correctly, but I believe energy efficiency in PSUs plummets when near or at full capacity (especially PSUs not very highly rated for efficiency -- there are particular internal components where, if used, efficiency is more "even" under different loads, but I don't remember what the components you're supposed to look for are called), so you should take that into consideration, too.

Completely agree with grobbes' post.


Title: Re: will 1200 watts run it?
Post by: grobbes on May 21, 2013, 02:06:08 AM
I think some people need to measure actual wattage at the wall :) Power requirements are pretty inflated on these boards in terms of wattage.

http://www.amazon.com/P3-International-P4400-Electricity-Monitor/dp/B00009MDBU/ref=sr_1_1?ie=UTF8&qid=1369102006&sr=8-1&keywords=kill+a+watt


Title: Re: will 1200 watts run it?
Post by: Kinetic915 on May 21, 2013, 03:14:38 AM
If voltage unlocked, you can usually drop about 50-60 watts a card. I run 4 7950s, dual core celeron, and raptor HD with room to spare. It's more important to get Gold level or above

put volt down 50 or 60 and clocks up?  still stable for you?


Title: Re: will 1200 watts run it?
Post by: Kinetic915 on May 21, 2013, 03:15:00 AM
I think some people need to measure actual wattage at the wall :) Power requirements are pretty inflated on these boards in terms of wattage.

http://www.amazon.com/P3-International-P4400-Electricity-Monitor/dp/B00009MDBU/ref=sr_1_1?ie=UTF8&qid=1369102006&sr=8-1&keywords=kill+a+watt

Oh i bought one of those asap  :D


Title: Re: will 1200 watts run it?
Post by: grobbes on May 21, 2013, 03:53:34 AM
If voltage unlocked, you can usually drop about 50-60 watts a card. I run 4 7950s, dual core celeron, and raptor HD with room to spare. It's more important to get Gold level or above

put volt down 50 or 60 and clocks up?  still stable for you?

Yeah, honestly it will take a bit of tweaking before finding the best ratio. 7970s like .57 core/mem ratio and around .79 for 7950s.

there's been some threads I can't find for best kw/h to profit ratio for these two cards but I can't seem to find them, sorry :(