[Solved] SLI GTX 570 with 750w PSU

Will a Corsair HX 750w with 62A on the +12V rail safely handle SLI 570s?

I'm thinking of getting a second GTX 570 but don't want to strain the t*ts of my power supply.

If I'd had a crystal ball when I built my computer and known I was going to be thinking about SLI GTX 570s I would of probably gone for a HX 850 but as I already own my HX 750 I can't afford to upgrade as well as get another graphics card.

The rest of my computer specs are in my signature if needed. Thanks in advance.

I wouldn't risk it, a 850W is a must for 2 high end cards in SLI. Maybe you could get away with 2 on 800W but seeing as you only have a 750W HX power suply, you might as well sell your GTX 570 and get a GTX 580 which should do you good on that monitor you have at 1080p. I have to say your build looks neat.

Or if you could, wait until AMD's new GPU's and get one of there high end 7000 series. It should be good to run on a single 750W PSU. You have a nice PSU there by the way, its quality and 90+ efficiency.

Good luck on your decision.

Reply to appleshaq

You would be pushing the psu past the magic 50% load number, if that matters to you go get a 900 watt psu.
If not, you're 750 will be somewhere in the 70% +/- load range when gaming, a quality unit like the HX 750 shouldn't have a problem with that.

Reply to delluser1

An HX850 would be a better choice, as it will give you some extra headroom. The HX750 is a high enough quality where you wont see much if any problems with efficiency or longevity from your PSU. I would recommend the HX850 though.

------------------------------ - Cooler Master HAF X
- Corsair HX750W
- ASUS Sabertooth 990FX
- Phenom IIx4 955BE
Reply to casualbuilder

If you want to objectively, accurately and scientifically determine what PSU power is required for your Vid card and PC in both watts and 12v rail amps., the forum Utility link below will show you how easy it is to calculate this information and objectively determine which PSUs are quality built, reliable PSUs that can meet your needs. Be advised that the available 12v rail amps. is just as important as the total PSU wattage. You need both to be correct.

http://www.tomshardware.com/forum/ [...] r-required

Message quoted 1 times

------------------------------ READ THIS: A GOOGLE SEARCH WILL ANSWER 98% OF ALL QUESTIONS ASKED IN FORUMS !

*** OVERCLOCKING IS A JOURNEY OF DISCOVERY FILLED WITH FRUSTRATION. IT IS NOT A DESTINATION. ***
Reply to beenthere

Best answer

Its is close, but I am sure you know that, as you yourself said, yes the 850 would have been a better choise, oh insight in a wonderfull thing.

Taken from Guru3D.

'Power consumption
Let's have a look at how much power draw we measure with this graphics card installed.

The methodology: We have a device constantly monitoring the power draw from the PC. We simply stress the GPU, not the processor. The before and after wattage will tell us roughly how much power a graphics card is consuming under load.

Our test system is based on a power hungry Core i7 965 / X58 system. This setup is overclocked to 3.75 GHz. Next to that we have energy saving functions disabled for this motherboard and processor (to ensure consistent benchmark results). On average we are using roughly 50 to 100 Watts more than a standard PC due to higher CPU clock settings, water-cooling, additional cold cathode lights etc.

Keep that in mind. Our normal system power consumption is higher than your average system.

Measured power consumption

System in IDLE = 181W
System Wattage with GPU in FULL Stress = 369W
Difference (GPU load) = 188W
Add average IDLE wattage ~ 25W
Subjective obtained GPU power consumption = ~ 213 Watts'

They go on to recomend a 600w PSU for a SINGLE CARD, no way!! I think alot of this is going to come down to OC/OV of the GPUs, I think you will be more than ok. Also to note the HX750 is a good PSU (prolly the best of the 750s to be honest) and its peak power will actually be higher than 750w.

If it was me, I would get the 2nd card.

Article is avaialble here: should you want to read it.
http://www.guru3d.com/article/geforce-gtx-570-review/8

Message quoted 1 times

Reply to Cygone

As stated above you'd be pushing it to the limits and it's not safe if any overclocking Occurs, from GURU3D

Quote :

GeForce GTX 570 in SLI

A second card requires you to add another 225 Watts. You need a 850+ Watt power supply unit if you use it in a high-end system (1 KiloWatt recommended if you plan on any overclocking).

Regardless the 1K PSU recommendation because it doesn't make any sense, you definitely need a 850W PSU

Message quoted 1 times

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Reply to ilysaml

ilysaml wrote :

As stated above you'd be pushing it to the limits and it's not safe if any overclocking Occurs, from GURU3D

Quote :

GeForce GTX 570 in SLI

A second card requires you to add another 225 Watts. You need a 850+ Watt power supply unit if you use it in a high-end system (1 KiloWatt recommended if you plan on any overclocking).

Regardless the 1K PSU recommendation because it doesn't make any sense, you definitely need a 850W PSU

Because Hilbert said so ?
:lol: :lol: :lol:

Message quoted 1 times

Reply to delluser1

With only 369w on total system (excluding CPU load), so another 150w,

369 +
150 +
213
=732w

Message quoted 1 times

Reply to Cygone

delluser1 wrote :

Because Hilbert said so ?
:lol: :lol: :lol:

I don't get it

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Reply to ilysaml

^ I highly disagree.

GTX580 Pulls 245W independently, 490W with SLI
i5 2500K pulls roughly 160W max with Moderate to High OC.

This is 650W, and honestly, i dont see any combination of drives or fans that will use 100W, so even for GTX580's there is ENOUGH. That being said, this is only a GTX570 config, so you have another 40W to use.

Message quoted 1 times

------------------------------ - Cooler Master HAF X
- Corsair HX750W
- ASUS Sabertooth 990FX
- Phenom IIx4 955BE
Reply to casualbuilder

as per this thread, you use about 150w on the CPU when its OCd

http://www.overclock.net/intel-cpu [...] our-2.html

Message edited by Cygone on 10-27-2011 at 04:17:26 PM

Reply to Cygone

casualbuilder wrote :

^ I highly disagree.

GTX580 Pulls 245W independently, 490W with SLI
i5 2500K pulls roughly 160W max with Moderate to High OC.

This is 650W, and honestly, i dont see any combination of drives or fans that will use 100W, so even for GTX580's there is ENOUGH. That being said, this is only a GTX570 config, so you have another 40W to use.

The CPU pulls 160w (I said 150w, so its thier or thier abouts), but this does not take into account, (again as you said, fans), but HDDs, ODDs, SSDs, RAMs, MOBO, UVs, Sound cards, Water Pumps,

Reply to Cygone

exactly...unless you had 2 drives, at least 3 HDDS and a huge stock of water pumps, and all those goodies, thats bull. I believe a blu-ray drive uses 60W, 7200RPM hdds use around 25W, at 1.65V RAM uses 21W. Thats 106W. Yes, its close, even pushing the threshhold, but the HX750 can over-power since it is such a stable psu, so it is enough...I would recommend the HX850 like i said way back towards the beginning of the thread.

"An HX850 would be a better choice, as it will give you some extra headroom. The HX750 is a high enough quality where you wont see much if any problems with efficiency or longevity from your PSU. I would recommend the HX850 though."

Message quoted 1 times

------------------------------ - Cooler Master HAF X
- Corsair HX750W
- ASUS Sabertooth 990FX
- Phenom IIx4 955BE
Reply to casualbuilder

Cygone wrote :

With only 369w on total system (excluding CPU load), so another 150w,

369 +
150 +
213
=732w

Not quite
I have a system kinda similar to Guru3D's
I7-930 @ 3.8
GTX 570 SC
3 x 2 Gb
1 x HD
1 x OD
1 x 120mm
Pulled my loop for maintenance, back to big air ( Tr IFX-14, dual LED fans ) pulling about 25 watts less from the wall now
open bench

Don't know what they're using to test, they won't divulge it for fear of some kind of conspiracy, but claim it is more like a gaming load.

My system draws 370 from the wall playing BFBC2 , that's about a 315 watt DC load when my psu's efficiency is factored in , add 213 ( most sites show 200 +/- ) to that.

Reply to delluser1

beenthere wrote :

If you want to objectively, accurately and scientifically determine what PSU power is required for your Vid card and PC in both watts and 12v rail amps., the forum Utility link below will show you how easy it is to calculate this information and objectively determine which PSUs are quality built, reliable PSUs that can meet your needs. Be advised that the available 12v rail amps. is just as important as the total PSU wattage. You need both to be correct.

http://www.tomshardware.com/forum/ [...] r-required

Thanks for the link.

According to your link my power supply should be ok. That is if the way to determine power required in the link is true, and I have worked it out correct.

"Say your Vid card draws 240W under max load. Divide 240 by 12 to get 20 amps. on the 12v rail. Add 15 amps. for the rest of the drives, fans, etc. and you have 35 amps. Add 5 more amps for a minimum safety margin when the PSU gets hot under full load and you end up needing <40+> amps. total on the 12v rails."

A GTX 570 uses 219w at load so 2 570s in SLI should use 438w?

438/12= 36.5 amps plus 15 amps for the the drives, fans, etc and 5 more amps for a minimum safety margin

36.5 + 20 = 56.5 amps

casualbuilder wrote :

exactly...unless you had 2 drives, at least 3 HDDS and a huge stock of water pumps, and all those goodies, thats bull. I believe a blu-ray drive uses 60W, 7200RPM hdds use around 25W, at 1.65V RAM uses 21W. Thats 106W. Yes, its close, even pushing the threshhold, but the HX750 can over-power since it is such a stable psu, so it is enough...I would recommend the HX850 like i said way back towards the beginning of the thread.

"An HX850 would be a better choice, as it will give you some extra headroom. The HX750 is a high enough quality where you wont see much if any problems with efficiency or longevity from your PSU. I would recommend the HX850 though."

According to Tomshardware http://www.tomshardware.com/review [...] 916-7.html

Current quad-core CPU, overclocked (High-end) = 140w
High-end motherboard board, overclocked = 55w
Current DDR2 or DDR3 RAM, per 4 GB module = 6w x 2 = 12w
Conventional hard drive = 10w
Current solid-state drives = 4 w
DVD burner = 10 w
CPU fan = 3w
Case fan = 3w x 6 = 18w
GTX 570 x2 = 438 w

Total = 690 w and 57.5 amps Is this right?

EDIT:

http://www.tomshardware.com/review [...] 16-11.html

This set up is similar to mine expect for the GTX 580 insted of a 570. With the Corsair AX 750 the computer peaked at 488w at load so evan adding a second 580 seems do able.

They also say "buying too big just to be on the safe side is counter-productive and only makes sense if you actually need the reserves"

Do I really need the reserves?

Message quoted 1 times
Message edited by Gothams Finest on 10-27-2011 at 05:21:49 PM

Cygone wrote :

Its is close, but I am sure you know that, as you yourself said, yes the 850 would have been a better choise, oh insight in a wonderfull thing.

They go on to recomend a 600w PSU for a SINGLE CARD, no way!! I think alot of this is going to come down to OC/OV of the GPUs, I think you will be more than ok. Also to note the HX750 is a good PSU (prolly the best of the 750s to be honest) and its peak power will actually be higher than 750w.

If it was me, I would get the 2nd card.

Article is avaialble here: should you want to read it.
http://www.guru3d.com/article/geforce-gtx-570-review/8

Thanks for the link

I don't understand why they recomend a 600w PSU for a single GTX 570 when they say

"Keep that in mind. Our normal system power consumption is higher than your average system."

and then go on to say the whole computer consumes 409w with FurMark.

"Now for those interested, the PC (not just graphics card) stressed with a game, consumes 369W and if we stress with FurMark we can write down a 409 Watt power consumption. So just Furmark alone used an extra 40W."

Gothams Finest wrote :

According to Tomshardware http://www.tomshardware.com/review [...] 916-7.html

Current quad-core CPU, overclocked (High-end) = 140w
High-end motherboard board, overclocked = 55w
Current DDR2 or DDR3 RAM, per 4 GB module = 6w x 2 = 12w
Conventional hard drive = 10w
Current solid-state drives = 4 w
DVD burner = 10 w
CPU fan = 3w
Case fan = 3w x 6 = 18w
GTX 570 x2 = 438 w

Total = 690 w and 57.5 amps

Is this right?

Excellent research on more viable numbers, i guestimated, but yes, this is very close to RL numbers, and you are correct in your thinking. 690/12 = 57.5, so a 62amp PSU will have plenty of juice, which is 750W.

------------------------------ - Cooler Master HAF X
- Corsair HX750W
- ASUS Sabertooth 990FX
- Phenom IIx4 955BE
Reply to casualbuilder