td (OP)
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May 13, 2011, 10:11:33 PM |
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How big of a power supply do I need for two 5870's? I see a lot of recommendations and people using 900 watt + for 5970's and such. Will these smaller requirements need that much power?
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keybaud
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May 13, 2011, 10:24:56 PM |
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I'm running 3 5870s off a 700 W PSU with an Intel E6400. At the wall I'm drawing 670 Watts, so I'm close to the limit, if not over it. I was drawing 280 Watts with one 5870, so each card is approx 185 Watts. I'm using a Coolermaster 700W Silent Pro, which is 80+ Gold certified and only cost £79 inc P&P in the UK.
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Sukrim
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May 13, 2011, 10:28:55 PM |
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Depending on the rest of your hardware you can expect that 2 5870 GPUs will draw ~200W each under load.
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mewantsbitcoins
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May 13, 2011, 10:33:50 PM |
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I'm running 3 5870s off a 700 W PSU with an Intel E6400. At the wall I'm drawing 670 Watts, so I'm close to the limit, if not over it. I was drawing 280 Watts with one 5870, so each card is approx 185 Watts. I'm using a Coolermaster 700W Silent Pro, which is 80+ Gold certified and only cost £79 inc P&P in the UK.
keybaud may I ask what motherboard you are using?
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keybaud
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May 13, 2011, 11:40:25 PM |
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Intel D975XBX. I got it off Ebay a week or so ago with the E6400, 2GB DDR 2 and a 320 GB HDD for the grand total of £55.
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mewantsbitcoins
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May 13, 2011, 11:41:47 PM |
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Thanks. I am looking for something that has the capacity for 3 cards
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compro01
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May 14, 2011, 02:31:30 AM |
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I'm running 3 5870s off a 700 W PSU with an Intel E6400. At the wall I'm drawing 670 Watts, so I'm close to the limit, if not over it. I was drawing 280 Watts with one 5870, so each card is approx 185 Watts. I'm using a Coolermaster 700W Silent Pro, which is 80+ Gold certified and only cost £79 inc P&P in the UK.
You've got a fair bit of headroom left. 670W wall at 87% efficiency is 582W of output, so you've got 118W of extra headroom, assuming your temps are in spec.
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ElectroGeek007
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May 14, 2011, 05:48:31 AM |
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I am also using the Intel D975XBX also; with an Intel E6300, 2GB DDR2 667, a reference 5850, and a non-reference Sapphire 5870, and this PS is serving me well (I don't have any exact usage figures, though): http://www.newegg.com/Product/Product.aspx?Item=N82E16817371026&cm_re=earthwatts-_-17-371-026-_-Product
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"And what the enemy will see, they will see the flash of our cannons, and they will hear the ringing of our swords, and they will know what we can do! By the sweat of our brow and the strength of our backs and the courage in our hearts! Gentlemen, hoist the colors!"
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bytemaster
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May 15, 2011, 02:17:12 PM |
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I think I just blew a 1200W power supply powering 2x Nvidia 295's just 18 hours after I started GPU mining. (At least I hope that is all I blew). It tripped the circuit breaker.
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1bitc0inplz
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May 15, 2011, 02:47:09 PM |
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What does reference and non-reference mean in this context? And how does that effect wattage?
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Orcworm
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May 15, 2011, 02:52:17 PM |
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I think I just blew a 1200W power supply powering 2x Nvidia 295's just 18 hours after I started GPU mining. (At least I hope that is all I blew). It tripped the circuit breaker.
What model PSU is it? What does reference and non-reference mean in this context? And how does that effect wattage? A reference GPU uses the 'stock' ATI / Nvidia board and heatsink, non-reference cards typically use boards that may restrict overclocking (By locking the voltage, for example) or they may have a custom cooler fitted.
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bytemaster
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May 15, 2011, 02:57:56 PM |
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I think I just blew a 1200W power supply powering 2x Nvidia 295's just 18 hours after I started GPU mining. (At least I hope that is all I blew). It tripped the circuit breaker.
What model PSU is it? Thermaltake W0133RU ToughPower 1200W Modular Power Supply
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bytemaster
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May 15, 2011, 03:05:02 PM |
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Assuming the power supplies are only 80% efficient, a 1200W supply is can really only provide 960W. Operating a power supply for extended periods of time near the upper end of its rated range is sure to find the weakest component.
So I would recommend sizing your power supply 30-50% more than it is actually using to prevent it from overheating or failing early.
In my case, I decided to replace it with the ToughPower 1350W supply, it was cheaper and has 10% more margin for error.
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Dyaheon
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May 15, 2011, 03:54:20 PM |
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Assuming the power supplies are only 80% efficient, a 1200W supply is can really only provide 960W.
No, what that means it can supply 1200W. Thus drawing 1500W from wall at 80% efficiency. Leaving some headroom is of course recommended. PSUs tend to get noisy at high loads, and tend to be most efficient around 50% load. So it's probably a good idea to leave some 20-30% headroom at least.
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SgtSpike
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May 16, 2011, 02:54:12 AM |
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On a related note, would a 650w PSU be necessary for running 3x5850's, or could I drop it down to a decent 550w or 500w? Recommendations? The other components would just be a 65TDP C2D, single stick of memory, and HDD/fans. Well, and the motherboard, obviously.
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aistto
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May 16, 2011, 03:46:16 AM |
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On a related note, would a 650w PSU be necessary for running 3x5850's, or could I drop it down to a decent 550w or 500w? Recommendations? The other components would just be a 65TDP C2D, single stick of memory, and HDD/fans. Well, and the motherboard, obviously.
if you going to OC your cards choose 650w PSU
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SgtSpike
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May 16, 2011, 03:46:47 AM |
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On a related note, would a 650w PSU be necessary for running 3x5850's, or could I drop it down to a decent 550w or 500w? Recommendations? The other components would just be a 65TDP C2D, single stick of memory, and HDD/fans. Well, and the motherboard, obviously.
if ypu going to OC your cards choose 650w PSU Yeah, good point. I do plan to overclock them.
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aistto
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May 16, 2011, 03:52:09 AM |
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On a related note, would a 650w PSU be necessary for running 3x5850's, or could I drop it down to a decent 550w or 500w? Recommendations? The other components would just be a 65TDP C2D, single stick of memory, and HDD/fans. Well, and the motherboard, obviously.
if ypu going to OC your cards choose 650w PSU Yeah, good point. I do plan to overclock them. btw, if you going to use 5870 bios your card will consume more than 150w. I think it about 160 - 170 w.
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