GTX 285 SLI Rig Total Power Draw

[Hauk]

Was wondering if my Corsair HX1000 would handle 285 Tri-Sli down the road, so I bought a Kill A Watt meter when I ordered two XFX 285's. I know the cheapie version of this Kill A Watt is not the most accurate tool available, but it's got to be fairly accurate right? Well.. the results were surprising.

Take a look at these specs, before you look at the results, take a guess what my idle and load power draw will be:

* Antec 1200, 6 120mm fans on low, 1 200m fan on low
* 2 Asus CD/DVD burners
* Asus Rampage II Extreme, all power saving functions disabled, full phase power setting
* i7 920 @ 3.74, 195 BCLCK, 1.29V
* 12GB OCZ DDR3 1600 8-8-8-24 1T
* 8GB OCZ Rally 2 Flash Drive
* 2 Super Talent 64GB SSD's in RAID 0
* X-Fi Titanium Fatal1ty Professional PCI-E
* XFX GTX 285 SLI @ 691/1573/2600

Some pics:

Rig

OCZ 12GB 1600 8-8-8-24 1T

XFX GTX 285 SLI

So we've read how nVidia goes overboard in specifying PSU's for their configs, and we've seen the latest GTX 285 reviews with power results included. Today I played through some demanding scenes in Far Cry 2. I'll try other games; I know power draw fluctuates slightly depending on application. But with good scaling and a lot of fire in the scene (fire seemed to produce the highest draw), I was surprised at my total draw at load. Okay okay, here are the results:


Total system watts at idle

Total system watts at load


So what do you think about that draw at load? Can it be right? Far Cry 2 is a fairly demanding application. It may not be Crysis, but from reviews I've seen, the fluctuations between applications varies by only a few watts. Opinions?

 

[toyota]

sounds about right. my system in sig idles at 81 watts and only pulls 187 watts at the wall during Far Cry 2 demo loop.

I dont really understand whats up with video card companies suggesting such ridiculous power supply requirements. even cards like 4670 and 9600gt suggest 400-450 watt power supplies. its hilarious to watch people buy a 750-1000 watt psu to run a mid range system.

to be honest most modest systems toady draw very little power at idle and full system load even with a midrange gpu and cpu. hell most cpus like mine even draw less power than decent cpus 5 years ago. sure video cards use more power but overall system loads on low and mid range comps are not much different than when a 250-300 watt power supply was the norm for mid range setups.

 

[MarcVenice]

Try dual orthos + vantage plz?

At 80% efficiency you're components are pulling 350W. 100W for each gpu +100W for the cpu, leaves 50W for the sdd's +ram +fans. Could be possible, but I doubt your gpu's +cpu are running at full steam.

Besides afaik the Kill-a-Watt isn't very good at measuring peaks, and there is also something abt ac/dc conversion. All in all I think your rig is pulling more then you think, but it should still be able to run tri-sli GTX285's.

 

[Hauk]

Ran alone, dual orthos load was about 320w. Vantage alone fluctuated, peaked around 450w. Together peak was around 503w. You're right, cpu/gpus are not fully stressed running FC2, and the kill-a-watt isn't the best tool; the result are interesting though!

 

[Rubycon]

Run Linpack + Furmark.

I don't know how Furmark does with dual GPU though.

My system draws over 705 watts from the socket (@ 230V) verified with a Dranetz power monitor that is very accurate. The box has a single GTX280 factory OC, QX9650 at 4.02GHz, 10 15K SAS drives on Areca ARC1680ix-24 with 2GB cache and 5 Seagate 1.5TB SATA drives. The 15 HDD's chew quite the power alone as the idle is over 350 watts. Power pack is 1,6kW U3 unit.

 

[Hauk]

Yea I'm just a gamer dude, not really looking to see how much load I can put on it, was mainly wanting to determine load during gaming. Even if the kill-a-watt is not the most accurate device, I can't imagine it's off by a terrible amount. Works for me. I was just surprised to see the actual power draw during gaming. So much for the psu brainwashing we undergo!

 

[OCGuy]

Yes. I have never seen my system go above 69% usage on the 750TX.

As far as PSU brainwashing, you are correct. People over-buy BIG TIME.

 

[Hauk]

I'd love to use a more accurate gauge though. Thanks for the tips Marc/Ruby... :thumbsup:

 

[Tempered81]

+1 for linx + furmark/atitool

 

[Rubycon]

Well you don't want to under buy either! If your max draw while gaming 2 hr/day is 500W a 650W PS is barely fit, 750W is better. The internal temperatures will run considerably cooler on a unit that is 60% loaded vs. 90% loaded, efficiency will be better and the unit will last longer.

But there are a lot of 1kW supplies on single GPU, systems with perhaps a pair of HDD and one optical drive. Definitely overkill but nothing wrong with that either. Compare that to the guy that blows all his cash on the latest and greatest CPU/GPU and relies on a Deer/Allied 450W generic PS! :Q Come on over! Gonna be a fireworks show! :laugh:

 

[nitromullet]

Yeah, something doesn't quite match up with the results you are getting and what the jonnyGURU guys were seeing with their 3-way SLI rig. http://www.jonnyguru.com/forum...p?p=41007&postcount=10

They are getting 737W at load with 3 GTX 280s, and you are seeing 433W with two... You are all using a Kill-a-watt, but it looks like they were running 3D Mark Vantage. I'm guessing that FC2 isn't pushing the system as hard as 3DMark Vantage...

 

[OCGuy]

Originally posted by: nitromullet
Yeah, something doesn't quite match up with the results you are getting and what the jonnyGURU guys were seeing with their 3-way SLI rig. http://www.jonnyguru.com/forum...p?p=41007&postcount=10

They are getting 737W at load with 3 GTX 280s, and you are seeing 433W with two... You are all using a Kill-a-watt, but it looks like they were running 3D Mark Vantage. I'm guessing that FC2 isn't pushing the system as hard as 3DMark Vantage...

285 has a lower TDP than 280.


I'm seeing ~518W max load with 2 280s.

 

[Hauk]

Originally posted by: Ocguy31
285 has a lower TDP than 280.

I'm seeing ~518W max load with 2 280s.

Yea that seems in line with this firing squad review that I looked at when configuring. Reviews seem to place 285 draw in line with 280 despite the TDP difference as claimed. My results would indicate a lower TDP but who knows, maybe just the toy of a power meter I bought.

One thing I've decided though, I'll not be getting a third 285. This thing is blazing fast. I'm gonna pretend Crysis doesn't exist and in doing so, I'm set until DX11 cards hit..

 

[MarcVenice]

Why pretend Crysis doesn't exist? It should look gorgeous on your rig, and still run at 30fps or higher.

 

[AmberClad]

Originally posted by: Rubycon
But there are a lot of 1kW supplies on single GPU, systems with perhaps a pair of HDD and one optical drive. Definitely overkill but nothing wrong with that either. Compare that to the guy that blows all his cash on the latest and greatest CPU/GPU and relies on a Deer/Allied 450W generic PS! :Q Come on over! Gonna be a fireworks show! :laugh:

PSUs are one of those things, along with hard drives and cases, that I dislike having to upgrade every year. So "overkill' > "just enough" in my case. It's not like 1kW PSUs are going to have a massive drop in price all of a sudden.

The other thing worth mentioning as far as why it's undesirable to have a power draw near the full capacity of the PSU -- the fan inside is going to be ramping up as it approaches the max capacity.

 

[nitromullet]

Originally posted by: Ocguy31

Originally posted by: nitromullet
Yeah, something doesn't quite match up with the results you are getting and what the jonnyGURU guys were seeing with their 3-way SLI rig. http://www.jonnyguru.com/forum...p?p=41007&postcount=10

They are getting 737W at load with 3 GTX 280s, and you are seeing 433W with two... You are all using a Kill-a-watt, but it looks like they were running 3D Mark Vantage. I'm guessing that FC2 isn't pushing the system as hard as 3DMark Vantage...

285 has a lower TDP than 280.


I'm seeing ~518W max load with 2 280s.

I didn't catch that they were 285s (coffee was still brewing)... Makes more sense then.

Originally posted by: AmberClad

Originally posted by: Rubycon
But there are a lot of 1kW supplies on single GPU, systems with perhaps a pair of HDD and one optical drive. Definitely overkill but nothing wrong with that either. Compare that to the guy that blows all his cash on the latest and greatest CPU/GPU and relies on a Deer/Allied 450W generic PS! :Q Come on over! Gonna be a fireworks show! :laugh:

PSUs are one of those things, along with hard drives and cases, that I dislike having to upgrade every year. So "overkill' > "just enough" in my case. It's not like 1kW PSUs are going to have a massive drop in price all of a sudden.

The other thing worth mentioning as far as why it's undesirable to have a power draw near the full capacity of the PSU -- the fan inside is going to be ramping up as it approaches the max capacity.

Both good points. I like my PSU to be ready for whatever I may throw at it. My current PSU was purchased with the intention of running dual 4870 X2s in Crossfire-X, but I things worked out differently. I like the knowledge that my PSU is not going to stand the way of whatever build I decide to go with for the foreseeable future. I think that is the main reason people go with a 1KW PSU.

 

[conlan]

I like the knowledge that my PSU is not going to stand the way of whatever build I decide to go with for the foreseeable future. I think that is the main reason people go with a 1KW PSU.

Agreed.

Remember, @ 500W actual system draw, your 1000W PSU is operating within it's peak efficiency range. Which in most PSUs is somewhere between 40 - 60% of total watts rating.

 

[Hauk]

Originally posted by: MarcVenice
Why pretend Crysis doesn't exist? It should look gorgeous on your rig, and still run at 30fps or higher.

Just like high frame rates in shooters. I've played Crysis and Warhead on high. It'd be too tempting to see if I could do very high & 60fps by adding a third 285. See, I'm already sorting it out mentally! Crysis = Bane

 

[Hauk]

Originally posted by: AmberClad

... The other thing worth mentioning as far as why it's undesirable to have a power draw near the full capacity of the PSU -- the fan inside is going to be ramping up as it approaches the max capacity.

Indeed. I ran into this once and it was annoying, an otherwise quiet rig and the psu was ruining the experience. I love this Corsair psu!

 

[ArchAngel777]

It is true that JonnyGuru did make note of measuring AC at the wall being sometimes incorrect and while true, it didn't really have any serious implications because the amount it was off buy was small. For instance the video he had showed 1000 watts IRRC being produced on the DC and showing slightly under (like 950 or something on the meter, but really at least 1200 due to conversion loss) on the AC. So, you do have the conversion loss. But if anything, that just means that if you are measuring with AC, don't take the conversion (* .8) into the consideration and use the AC numbers as your DC numbers. Until someone can show me these things producing far, far greater DC power than what is being read off the AC meter, then the fact some of these are 'not as accurate' doesn't really matter because they have the right ball park figure.

What I am trying to say is that I agree with OCGuy and Hauk at this point. *Some* people do have need of those 800 watt monsters, but most of us can get buy on a cheapo 450/500 watt. But, I also agree that buying extra makes it so you don't have to upgrade that PSU all the time.

 

[Zap]

Originally posted by: toyota
I dont really understand whats up with video card companies suggesting such ridiculous power supply requirements.

Lowest common denominator.

Brand A 500W PSU may only output a true 25A of +12v power at normal operating temperatures while Brand B 500W PSU may output a true 35A of +12v power at normal operating temperatures. If Brand A is assumed, then both brands will work.

Originally posted by: Rubycon
I don't know how Furmark does with dual GPU though.

No SLI profile by default, though you can create one.

Originally posted by: Rubycon
10 15K SAS drives on Areca ARC1680ix-24 with 2GB cache and 5 Seagate 1.5TB SATA drives. The 15 HDD's chew quite the power alone

Wow, you can power another GPU or two with that. :Q

Originally posted by: ArchAngel777
most of us can get buy on a good quality 450/500 watt

Fixed.

Nobody should be using a "cheapo" PSU. There is quality (or lack thereof) and there is output.

Not to say there aren't any "inexpensive" PSUs.

 

[toyota]

Originally posted by: Zap

Originally posted by: toyota
I dont really understand whats up with video card companies suggesting such ridiculous power supply requirements.

Lowest common denominator.

Brand A 500W PSU may only output a true 25A of +12v power at normal operating temperatures while Brand B 500W PSU may output a true 35A of +12v power at normal operating temperatures. If Brand A is assumed, then both brands will work.

Originally posted by: Rubycon
I don't know how Furmark does with dual GPU though.

No SLI profile by default, though you can create one.

Originally posted by: Rubycon
10 15K SAS drives on Areca ARC1680ix-24 with 2GB cache and 5 Seagate 1.5TB SATA drives. The 15 HDD's chew quite the power alone

Wow, you can power another GPU or two with that. :Q

Originally posted by: ArchAngel777
most of us can get buy on a good quality 450/500 watt

Fixed.

Nobody should be using a "cheapo" PSU. There is quality (or lack thereof) and there is output.

Not to say there aren't any "inexpensive" PSUs.

a cheapo psu is usually fine with a cheapo system though. I still have a Compaq pc from 2003 with the oem 250watt psu and that thing has powered 5700, 6600, and 7600 cards and is still going strong.

 

[ArchAngel777]

Originally posted by: Zap

Originally posted by: ArchAngel777
most of us can get buy on a good quality 450/500 watt

Fixed.

Nobody should be using a "cheapo" PSU. There is quality (or lack thereof) and there is output.

Not to say there aren't any "inexpensive" PSUs.

Going to have to dissagree here. My company also builds systems and they are in very hazardous environments. Never, have we had a PSU blow up and take a system with it. We have, however, had Power Supples go bad from time to time, but then again, that is expected when you run in a hazardous environment. With inches thick of dust created each day, no power supply will stand up to that and will eventually fail prematurely. Everyone talks about a Power Supply taking out their system - maybe it can, but I have never seen it out of the thousands of PC's I have supported in the past. When a PSU dies, it dies pretty friendly death from what I have seen. Maybe a pop or a bang... Put a new PSU in, system purrs like a kitten again.

I can't say I recomend using a cheapo power supply, but I also can't say other than living a shorter life, that it will have any other affect on a user. Maybe one day it won't power your system anymore, or maybe some system instability pops up, that would be more likely to happen on a cheap power supply, but honestly, in my experience that is something rather rare. I am also not pulling experience from my personal system builds, I am pulling it from work experience who has assembled, built and supported thousands over the years which operated in harsh environments. Auto Body Shops, Mechanical Shops, Paint Shops. If you have ever been in one, you would know that instantly, it is probably one of the worst environments for a PC to be in. They typically are very, very hot in the summer and inches of dust are produced each day from the bondo that is sanded off. The dust is also so fine, that most filters cannot even keep it out.

But if I am going to build a system for a friend or for myself? I won't get a gutter PSU, but I am also not going to recomend overkill either. But to each their own.

In way, I see the arguement similar to what DuPont Automotive does. They make sure all their equipment is intrinsicly safe, Class I Division I - explosion proof. In other words, there is no way their equipment will cause a paint mixing room to go up in a blaze. However, PPG, Sickens, Shirwin Williams, etc... They don't follow such strict guidelines for their equipment and in theory, it could cause an explosion, no matter how rare. But the truth is, when have you heard on the news that a paint mixing room went up in a blaze? I have never seen it and since DuPont Automotive only has around 40% of the market share then we know that only they provide the Class I Division I explosion proof techniques. So, I see the arguement similar to power supplies. It 'can' cause things and it 'might' but the probability is low either way. *Shrug* again, to each their own.

 

[biostud]

Originally posted by: ArchAngel777
*Some* people do have need of those 800 watt monsters, but most of us can get buy on a cheapo 450/500 watt.

and by cheapo you mean high quality low wattage PSU, right?

 

[Tempered81]

Originally posted by: Zap
Nobody should be using a "cheapo" PSU. There is quality (or lack thereof) and there is output.

Not to say there aren't any "inexpensive" PSUs.

I agree. Just returned an HEC Zephyr 750watt piece of crap for a Corsair 650. The cheapo psu wouldn't even maintain my cpu & gpu over-volted.

I would strong recommend anyone to purchase a NAME BRAND TOP QUALITY PSU. -because if you don't you will just end up rma'ing your cheapo piece of shit and buying one later. And feel like a boob for not taking sound advice and instead buying crap in the first place (which is how i feel)