gtx 780 ti sli power consumption

[lostmish]

i have an 875watt power supply and was wondering if it can handle 2 gtx 780 ti in sli?
in case u need to know i have a 3960x cpu

 

[lp231]

What PSU do you have?

 

[rolli59]

These are total system loads so if the 875watts is quality it will work http://anandtech.com/show/7492/the-geforce-gtx-780-ti-review/15

 

[lostmish]

What PSU do you have?

I dont know what psu i have i got it from alienware but in their site you can choose to have two gtx 780s sli but no option for 780ti thats why in asking

 

[lp231]

Just open up your case and look at the label.
If it can support GTX 780 in SLI, then there should be no problems running a pair of GTX 780Ti in SLI.
This should be the PSU used in Alienware (from Dell forums)

 

[lostmish]

Just open up your case and look at the label.
If it can support GTX 780 in SLI, then there should be no problems running a pair of GTX 780Ti in SLI.
This should be the PSU used in Alienware (from Dell forums)

yes thats my psu. Thanks alot for your help ill go ahead and buy myself a pair of gtx 780ti right now

 

[rolli59]

Yes with 825watts on the combined +12 volt rail it should handle it fine.

 

[RigRebel]

When loading PSU with multiple GPU's (on a gaming rig) one of the two most important (and most often missed) "power" factors when picking out a power supply are 1. AMPs and 2. How many Amps on each 12Volt rail , or to be precise, getting the maximum amount of amperage on a (preferred) single volt rail. Multiple rail PSUs, (IMO) are more for servers or for those that wish redundant power across multiple rails incase one or two rails fails. Also, multiple PSUs (IMO) I are cheaper and cheaper to manufacture. Not to mention, that if power across multi rails is not all used it's wasted. For gaming (and especially SLI/Xfire) I ALWAYS recommend one single twelve volt + rail. Now some may say well if that rail dies then the PSU is dead and that's correct, but gaming at max with 2 cards on a multi-rail system that's lost a rail will most likely fail/crash anyways.

Now, as far as "enough power" I tend to go by AMPERAGE not wattage. All high end video cards have a recommended (amperage) to them, it may be hard to find in the specs but they do. This is more important of a number to go by because you can have two 500 watt power supplies and one have 22amps and one have 30amps. If the card you have requires a 25amp minimum, you're more likely to crash at extended periods of max gaming on the 22amp PSU. And, it's tricky because sometimes a manufacturer will say "minimum 500w" but one has less amperage (less current strength) than the other and may not support the max load, especially in SLI/Xfire. Side note, most "GOOD" power supplies, will hold steady a little past there posted values and have some room to push it, GOOD ONES. Crappy ones are probably over rated and preform less than posted values or not at a constant rate.

A handy (but general) formula for figuring out how much amps are in a unit is Total Number of Watts/12 (Volts for the rail) = Amps... so a 875Watt PSU would have 72 amps... NOW, for a GEFORCE 780 I believe the minimum recommended amount of Amps for that card is 40... now, the second card won't run at exactly the same TDP as the first card but at 72 amps you are REALLY close to the limit. To be safe, I'd give yourself some more head room, if it's not too late, and go with an 80 or 85 amp unit with a single +12v rail and if you want to really be safe go with Silver or Gold rated because they more efficient with more constant values and without as much minor current loss as lower rated PSUs.

If you REALLY want to learn a WHOLE LOT about power supplies go here and read this > http://www.hardwaresecrets.com/article/Anatomy-of-Switching-Power-Supplies/327
it's my favorite site with the best info IMO about power supplies and reviews. EXCELLENT SITE.

Hope it helps.

At least that's my jist of it.

 

[rolli59]

When loading PSU with multiple GPU's (on a gaming rig) one of the two most important (and most often missed) "power" factors when picking out a power supply are 1. AMPs and 2. How many Amps on each 12Volt rail , or to be precise, getting the maximum amount of amperage on a (preferred) single volt rail. Multiple rail PSUs, (IMO) are more for servers or for those that wish redundant power across multiple rails incase one or two rails fails. Also, multiple PSUs (IMO) I are cheaper and cheaper to manufacture. Not to mention, that if power across multi rails is not all used it's wasted. For gaming (and especially SLI/Xfire) I ALWAYS recommend one single twelve volt + rail. Now some may say well if that rail dies then the PSU is dead and that's correct, but gaming at max with 2 cards on a multi-rail system that's lost a rail will most likely fail/crash anyways.

Now, as far as "enough power" I tend to go by AMPERAGE not wattage. All high end video cards have a recommended (amperage) to them, it may be hard to find in the specs but they do. This is more important of a number to go by because you can have two 500 watt power supplies and one have 22amps and one have 30amps. If the card you have requires a 25amp minimum, you're more likely to crash at extended periods of max gaming on the 22amp PSU. And, it's tricky because sometimes a manufacturer will say "minimum 500w" but one has less amperage (less current strength) than the other and may not support the max load, especially in SLI/Xfire. Side note, most "GOOD" power supplies, will hold steady a little past there posted values and have some room to push it, GOOD ONES. Crappy ones are probably over rated and preform less than posted values or not at a constant rate.

A handy (but general) formula for figuring out how much amps are in a unit is Total Number of Watts/12 (Volts for the rail) = Amps... so a 875Watt PSU would have 72 amps... NOW, for a GEFORCE 780 I believe the minimum recommended amount of Amps for that card is 40... now, the second card won't run at exactly the same TDP as the first card but at 72 amps you are REALLY close to the limit. To be safe, I'd give yourself some more head room, if it's not too late, and go with an 80 or 85 amp unit with a single +12v rail and if you want to really be safe go with Silver or Gold rated because they more efficient with more constant values and without as much minor current loss as lower rated PSUs.

If you REALLY want to learn a WHOLE LOT about power supplies go here and read this > http://www.hardwaresecrets.com/article/Anatomy-of-Switching-Power-Supplies/327
it's my favorite site with the best info IMO about power supplies and reviews. EXCELLENT SITE.

Hope it helps.

At least that's my jist of it.

The 40amp is for the whole system so the second card needs a lot less or each card peaks at 328watts http://www.techpowerup.com/reviews/ASUS/GTX_780_Ti_Direct_Cu_II_OC/21.html which equals 27.33 amps wich makes 2 cards consume only 54.66amps under stress test. Here is actually total system power consumption measured with 2 x 780Ti in SLI maxing at 654watts so OP is fine http://anandtech.com/show/7492/the-geforce-gtx-780-ti-review/15

 

[RigRebel]

When loading PSU with multiple GPU's (on a gaming rig) one of the two most important (and most often missed) "power" factors when picking out a power supply are 1. AMPs and 2. How many Amps on each 12Volt rail , or to be precise, getting the maximum amount of amperage on a (preferred) single volt rail. Multiple rail PSUs, (IMO) are more for servers or for those that wish redundant power across multiple rails incase one or two rails fails. Also, multiple PSUs (IMO) I are cheaper and cheaper to manufacture. Not to mention, that if power across multi rails is not all used it's wasted. For gaming (and especially SLI/Xfire) I ALWAYS recommend one single twelve volt + rail. Now some may say well if that rail dies then the PSU is dead and that's correct, but gaming at max with 2 cards on a multi-rail system that's lost a rail will most likely fail/crash anyways.

Now, as far as "enough power" I tend to go by AMPERAGE not wattage. All high end video cards have a recommended (amperage) to them, it may be hard to find in the specs but they do. This is more important of a number to go by because you can have two 500 watt power supplies and one have 22amps and one have 30amps. If the card you have requires a 25amp minimum, you're more likely to crash at extended periods of max gaming on the 22amp PSU. And, it's tricky because sometimes a manufacturer will say "minimum 500w" but one has less amperage (less current strength) than the other and may not support the max load, especially in SLI/Xfire. Side note, most "GOOD" power supplies, will hold steady a little past there posted values and have some room to push it, GOOD ONES. Crappy ones are probably over rated and preform less than posted values or not at a constant rate.

A handy (but general) formula for figuring out how much amps are in a unit is Total Number of Watts/12 (Volts for the rail) = Amps... so a 875Watt PSU would have 72 amps... NOW, for a GEFORCE 780 I believe the minimum recommended amount of Amps for that card is 40... now, the second card won't run at exactly the same TDP as the first card but at 72 amps you are REALLY close to the limit. To be safe, I'd give yourself some more head room, if it's not too late, and go with an 80 or 85 amp unit with a single +12v rail and if you want to really be safe go with Silver or Gold rated because they more efficient with more constant values and without as much minor current loss as lower rated PSUs.

If you REALLY want to learn a WHOLE LOT about power supplies go here and read this > http://www.hardwaresecrets.com/article/Anatomy-of-Switching-Power-Supplies/327
it's my favorite site with the best info IMO about power supplies and reviews. EXCELLENT SITE.

Hope it helps.

At least that's my jist of it.

The 40amp is for the whole system so the second card needs a lot less or each card peaks at 328watts http://www.techpowerup.com/reviews/ASUS/GTX_780_Ti_Direct_Cu_II_OC/21.html which equals 27.33 amps wich makes 2 cards consume only 54.66amps under stress test. Here is actually total system power consumption measured with 2 x 780Ti in SLI maxing at 654watts so OP is fine http://anandtech.com/show/7492/the-geforce-gtx-780-ti-review/15

I am confused... It does not appear to 40amps for total system according to this statement on the specs for an EVGA GTX 780 on new egg. Here's the quote >

"600 watt or greater power supply with a minimum of 42 amps on the +12 volt rail.
One 8-pin PCI Express power connector or two available 6-pin PCI Express power connectors and one 6-pin PCI Express power connector or two available hard disk power connector."

Here's the link > http://www.newegg.com/Product/Product.aspx?Item=N82E168...

You'll notice it says "42amps on the +12V" also...the entire system is not fed by +12V rail. If I remember correctly the +3v or +5V feeds the cpu and some other components but it's been a while since I researched it can't remember and in a hurry so can't look atm. However, it would appear that Newegg add is stating the card needs a minimum of 42amps so I am not clear about what you mean by 40amps for total system ? Did you mean that with a single card running the entire system will Draw 40amps ? Well if so, doesn't that still mean you would need 40amps (or in the GTX 780 link above 42amps) to run the card since the card can't run without the system ? lol. I do agree with you that the second card in SLI does not require as much amps as the first card. In fact, I did say "now, the second card won't run at exactly the same TDP " in my post.

I think I get what you mean though and I do see by this article http://www.guru3d.com/articles_pages/gtx_780_ti_sli_gef...

Both GTX 780 cards running in SLI caused a TDP for the CARDS THEMSELVES at 508 watts and the Total system draw was 617Watts. I know test vary from review to review but the 508watts is even less amperage required than the 54.6 amps you mentioned below. But good to know and thank you for expanding on my quantitative values.

My main point to the readers is that going by Wattage alone is a more general approach to picking a proper PSU and if you want to dig deeper or you're going to do SLI, taking a closer look at amperage might be worth the consideration; especially, if you're dumping gobs of $$$ on a high end SLI/Xfire system and have multiple PSU candidates to consider, wouldn't you want the most amperage for the $$$ ? I know I do, that's why when I spend money on a PSU I also look at which one is rated better on amperage and I love a single +12V rail personally.

But your info is good to know and thank you for clarify what the manufacture's sales statements and expanding on my general (and apparently incorrect) quantitative values.
Sorry my reply sloppy in a hurry.

 

[rolli59]

When loading PSU with multiple GPU's (on a gaming rig) one of the two most important (and most often missed) "power" factors when picking out a power supply are 1. AMPs and 2. How many Amps on each 12Volt rail , or to be precise, getting the maximum amount of amperage on a (preferred) single volt rail. Multiple rail PSUs, (IMO) are more for servers or for those that wish redundant power across multiple rails incase one or two rails fails. Also, multiple PSUs (IMO) I are cheaper and cheaper to manufacture. Not to mention, that if power across multi rails is not all used it's wasted. For gaming (and especially SLI/Xfire) I ALWAYS recommend one single twelve volt + rail. Now some may say well if that rail dies then the PSU is dead and that's correct, but gaming at max with 2 cards on a multi-rail system that's lost a rail will most likely fail/crash anyways.

Now, as far as "enough power" I tend to go by AMPERAGE not wattage. All high end video cards have a recommended (amperage) to them, it may be hard to find in the specs but they do. This is more important of a number to go by because you can have two 500 watt power supplies and one have 22amps and one have 30amps. If the card you have requires a 25amp minimum, you're more likely to crash at extended periods of max gaming on the 22amp PSU. And, it's tricky because sometimes a manufacturer will say "minimum 500w" but one has less amperage (less current strength) than the other and may not support the max load, especially in SLI/Xfire. Side note, most "GOOD" power supplies, will hold steady a little past there posted values and have some room to push it, GOOD ONES. Crappy ones are probably over rated and preform less than posted values or not at a constant rate.

A handy (but general) formula for figuring out how much amps are in a unit is Total Number of Watts/12 (Volts for the rail) = Amps... so a 875Watt PSU would have 72 amps... NOW, for a GEFORCE 780 I believe the minimum recommended amount of Amps for that card is 40... now, the second card won't run at exactly the same TDP as the first card but at 72 amps you are REALLY close to the limit. To be safe, I'd give yourself some more head room, if it's not too late, and go with an 80 or 85 amp unit with a single +12v rail and if you want to really be safe go with Silver or Gold rated because they more efficient with more constant values and without as much minor current loss as lower rated PSUs.

If you REALLY want to learn a WHOLE LOT about power supplies go here and read this > http://www.hardwaresecrets.com/article/Anatomy-of-Switching-Power-Supplies/327
it's my favorite site with the best info IMO about power supplies and reviews. EXCELLENT SITE.

Hope it helps.

At least that's my jist of it.

The 40amp is for the whole system so the second card needs a lot less or each card peaks at 328watts http://www.techpowerup.com/reviews/ASUS/GTX_780_Ti_Direct_Cu_II_OC/21.html which equals 27.33 amps wich makes 2 cards consume only 54.66amps under stress test. Here is actually total system power consumption measured with 2 x 780Ti in SLI maxing at 654watts so OP is fine http://anandtech.com/show/7492/the-geforce-gtx-780-ti-review/15

I am confused... It does not appear to 40amps for total system according to this statement on the specs for an EVGA GTX 780 on new egg. Here's the quote >

"600 watt or greater power supply with a minimum of 42 amps on the +12 volt rail.
One 8-pin PCI Express power connector or two available 6-pin PCI Express power connectors and one 6-pin PCI Express power connector or two available hard disk power connector."

Here's the link > http://www.newegg.com/Product/Product.aspx?Item=N82E168...

You'll notice it says "42amps on the +12V" also...the entire system is not fed by +12V rail. If I remember correctly the +3v or +5V feeds the cpu and some other components but it's been a while since I researched it can't remember and in a hurry so can't look atm. However, it would appear that Newegg add is stating the card needs a minimum of 42amps so I am not clear about what you mean by 40amps for total system ? Did you mean that with a single card running the entire system will Draw 40amps ? Well if so, doesn't that still mean you would need 40amps (or in the GTX 780 link above 42amps) to run the card since the card can't run without the system ? lol. I do agree with you that the second card in SLI does not require as much amps as the first card. In fact, I did say "now, the second card won't run at exactly the same TDP " in my post.

I think I get what you mean though and I do see by this article http://www.guru3d.com/articles_pages/gtx_780_ti_sli_gef...

Both GTX 780 cards running in SLI caused a TDP for the CARDS THEMSELVES at 508 watts and the Total system draw was 617Watts. I know test vary from review to review but the 508watts is even less amperage required than the 54.6 amps you mentioned below. But good to know and thank you for expanding on my quantitative values.

My main point to the readers is that going by Wattage alone is a more general approach to picking a proper PSU and if you want to dig deeper or you're going to do SLI, taking a closer look at amperage might be worth the consideration; especially, if you're dumping gobs of $$$ on a high end SLI/Xfire system and have multiple PSU candidates to consider, wouldn't you want the most amperage for the $$$ ? I know I do, that's why when I spend money on a PSU I also look at which one is rated better on amperage and I love a single +12V rail personally.

But your info is good to know and thank you for clarify what the manufacture's sales statements and expanding on my general (and apparently incorrect) quantitative values.
Sorry my reply sloppy in a hurry.

600watt with 42 amp on the +12 volt actually means for the total system! If you think of it this way the card gets 75 watts through the slot, 75 watts through a 6 pin connector and 150 watts through a 8 pin connector it maxes out at 300watt.

 

[RigRebel]

When loading PSU with multiple GPU's (on a gaming rig) one of the two most important (and most often missed) "power" factors when picking out a power supply are 1. AMPs and 2. How many Amps on each 12Volt rail , or to be precise, getting the maximum amount of amperage on a (preferred) single volt rail. Multiple rail PSUs, (IMO) are more for servers or for those that wish redundant power across multiple rails incase one or two rails fails. Also, multiple PSUs (IMO) I are cheaper and cheaper to manufacture. Not to mention, that if power across multi rails is not all used it's wasted. For gaming (and especially SLI/Xfire) I ALWAYS recommend one single twelve volt + rail. Now some may say well if that rail dies then the PSU is dead and that's correct, but gaming at max with 2 cards on a multi-rail system that's lost a rail will most likely fail/crash anyways.

Now, as far as "enough power" I tend to go by AMPERAGE not wattage. All high end video cards have a recommended (amperage) to them, it may be hard to find in the specs but they do. This is more important of a number to go by because you can have two 500 watt power supplies and one have 22amps and one have 30amps. If the card you have requires a 25amp minimum, you're more likely to crash at extended periods of max gaming on the 22amp PSU. And, it's tricky because sometimes a manufacturer will say "minimum 500w" but one has less amperage (less current strength) than the other and may not support the max load, especially in SLI/Xfire. Side note, most "GOOD" power supplies, will hold steady a little past there posted values and have some room to push it, GOOD ONES. Crappy ones are probably over rated and preform less than posted values or not at a constant rate.

A handy (but general) formula for figuring out how much amps are in a unit is Total Number of Watts/12 (Volts for the rail) = Amps... so a 875Watt PSU would have 72 amps... NOW, for a GEFORCE 780 I believe the minimum recommended amount of Amps for that card is 40... now, the second card won't run at exactly the same TDP as the first card but at 72 amps you are REALLY close to the limit. To be safe, I'd give yourself some more head room, if it's not too late, and go with an 80 or 85 amp unit with a single +12v rail and if you want to really be safe go with Silver or Gold rated because they more efficient with more constant values and without as much minor current loss as lower rated PSUs.

If you REALLY want to learn a WHOLE LOT about power supplies go here and read this > http://www.hardwaresecrets.com/article/Anatomy-of-Switching-Power-Supplies/327
it's my favorite site with the best info IMO about power supplies and reviews. EXCELLENT SITE.

Hope it helps.

At least that's my jist of it.

The 40amp is for the whole system so the second card needs a lot less or each card peaks at 328watts http://www.techpowerup.com/reviews/ASUS/GTX_780_Ti_Direct_Cu_II_OC/21.html which equals 27.33 amps wich makes 2 cards consume only 54.66amps under stress test. Here is actually total system power consumption measured with 2 x 780Ti in SLI maxing at 654watts so OP is fine http://anandtech.com/show/7492/the-geforce-gtx-780-ti-review/15

I am confused... It does not appear to 40amps for total system according to this statement on the specs for an EVGA GTX 780 on new egg. Here's the quote >

"600 watt or greater power supply with a minimum of 42 amps on the +12 volt rail.
One 8-pin PCI Express power connector or two available 6-pin PCI Express power connectors and one 6-pin PCI Express power connector or two available hard disk power connector."

Here's the link > http://www.newegg.com/Product/Product.aspx?Item=N82E168...

You'll notice it says "42amps on the +12V" also...the entire system is not fed by +12V rail. If I remember correctly the +3v or +5V feeds the cpu and some other components but it's been a while since I researched it can't remember and in a hurry so can't look atm. However, it would appear that Newegg add is stating the card needs a minimum of 42amps so I am not clear about what you mean by 40amps for total system ? Did you mean that with a single card running the entire system will Draw 40amps ? Well if so, doesn't that still mean you would need 40amps (or in the GTX 780 link above 42amps) to run the card since the card can't run without the system ? lol. I do agree with you that the second card in SLI does not require as much amps as the first card. In fact, I did say "now, the second card won't run at exactly the same TDP " in my post.

I think I get what you mean though and I do see by this article http://www.guru3d.com/articles_pages/gtx_780_ti_sli_gef...

Both GTX 780 cards running in SLI caused a TDP for the CARDS THEMSELVES at 508 watts and the Total system draw was 617Watts. I know test vary from review to review but the 508watts is even less amperage required than the 54.6 amps you mentioned below. But good to know and thank you for expanding on my quantitative values.

My main point to the readers is that going by Wattage alone is a more general approach to picking a proper PSU and if you want to dig deeper or you're going to do SLI, taking a closer look at amperage might be worth the consideration; especially, if you're dumping gobs of $$$ on a high end SLI/Xfire system and have multiple PSU candidates to consider, wouldn't you want the most amperage for the $$$ ? I know I do, that's why when I spend money on a PSU I also look at which one is rated better on amperage and I love a single +12V rail personally.

But your info is good to know and thank you for clarify what the manufacture's sales statements and expanding on my general (and apparently incorrect) quantitative values.
Sorry my reply sloppy in a hurry.

600watt with 42 amp on the +12 volt actually means for the total system! If you think of it this way the card gets 75 watts through the slot, 75 watts through a 6 pin connector and 150 watts through a 8 pin connector it maxes out at 300watt.

Ok gotcha, so theoretically, based on the guru3D report I showed for 2 GTX 780's in SLI showing a total power draw of 617W = 51.41 Amps my Seasonic X650 gold rated at 54amps (but capable of past 60amps in real world test) should also be able to handle 2 GTX 780's in SLi ?