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I've currently got 3 5850's running on a Phenom 2 x4 with 8gb RAM, on a 700w Corsair PSU.

I'm finding very conflicted information, some people seem to suggest 4 will run on a 700-750w unit while others are doing calculations of the power unit which suggest that i'd need an 850w or more.

Is anyone running a similar setup? Or could anyone test this out for me?

I have the 4th card just sitting , waiting for a PCIE x4 to x16 riser card so i can actually plug it in, but it will take a few more days to arrive, so if i need to go out and spend another £70+ on a PSU i'd rather get that done asap.

Thanks

You can use a 1000w PSU to handle 4x5850's I use the Antec 1000W

http://www.newegg.com/Product/Product.aspx?Item=N82E16817371012

If you dont want to think about it, a simple rule of thumb is 300 for the system, 200 per card. This is a bit of overkill but it will work no matter the card or overclock.

as for your system toms hardware did tests and with two, they found a draw of 469 (http://www.tomshardware.com/reviews/radeon-hd-5850,2433-13.html) with 1 card being 300 watts max. so 160 difference.

so for 4 cards.. 469 + 320 = 789 max watts

this is without overclock.. if you dont overvolt  a 1000 watter will be fine, if you overvolt, then you probably want a 1100 or 1200 watts

i have 3x5850 and 1x5870 running on a corsair 800w psu
all overclocked with default voltages

I'm sure i've read that the 5850's are the most power efficient in the 58XX group, would you know how much extra power your 5870 takes over the 5850's?


I forgot to mention one thing, i'm currently overclocking the core of each card to 840MHz and underclocking the memory to 150MHz (I know everyone says 300 is great, but i don't seem to be able to overclock the core any higher under any memory setting without a bsod, and there's no difference in hash rate between 300 and 150, but the temp goes down alot).

I don't know if downclocking the memory will make much of a difference at all, would anyone else know?

One more thing i need to ask;

I've just had some PCIE x4 to x16 riser cards arrive, if i tried to put my 4th card in my setup and there wasn't enough power, would it be safe? Would the pc simply not turn on / turn itself off, or would anything blow up?

A decent 1KW is plenty i say. I got 4 cards up on a decent 750 for 2x plus the system and a 650w bogo powering the other 2 cards. Wither way you look at it, its £150, least in the uk :)

I fried a 850 bogo psu with 3 cards. Didnt even do 2 :)

Wow so your 850w psu wouldn't cover 3 cards? Which cards were you trying it with?

I've just got a power reading for my rig, it's using 540-560w at the moment, that's the 3 5850's (840 core, 150 mem) a phenom 2 x4 and 8gb ram...

I've heard that 5850's can run at 150w, if so then i might be able to get away with sticking that in my machine right?

I can try downclocking the processor to see if that frees up any space.

my rig with 4x5830 sapphires with clocks 1000/300 have power consumption = 786 W

other with 4x5850 OC = 640 W  

this is power consumption "from wall"

What are you overlocking the 5850's to? It seems i should be able to get my 4th card working in this rig if i get a similar power usage to you :)

the 850 was a cheap nasty one for 60 quid. give.it a go :) fried in 2 mins ha ha. now I use xfx 750 and a basic 650. what was to hand :)

as i said, a decent kilowatt one will be more than enough

all 5800 cards pretty much use the same amount of power assuming the same voltages and clocks are being used
the 5870 is the most efficient one

1000 is probably a good idea, need to keep it below 80% load or so, to maintain peak power efficiency...

Not only the load, but the energy-efficiency are also important!

If you want a Corsair, buy one "Professional Series Gold" (http://www.corsair.com/power-supplies/modular-psus.html) series, but I would also recommend Cooler Master's Silent Pro Gold (http://www.coolermaster.com/product.php?product_id=6662) series...

I would recommended 1000-1200W for higher efficiency.

Edit: They have the best feature for mutly-GPU:

im powering them with 2x fortron fsp650-80egn per rig

i would stick to an 1250 if u overclocked some cards

hey i have almost the same exact setup. running 3x 5850 and 1x 5870 all overclocked, one 5850 overvolted, using a OCZ 850w gold efficiency. it draws about 750w from the wall.

Could someone please tell me how to overclock my 5850's past the 775 core that is max setting in CCC

Manythanks

I suggest you to buy a power metre, which can be found in most computer shops (or shopfront of electricity company), cheap and accurate, and you can avoid wasting tons of money on expensive PSU.

That seems high.  My 4x5830 Sapphires with clocks at 998/300 are 640W-650W at the wall with a Kill-A-Watt meter.

Cheers,
Kermee

maybe that difference comes from method used to count energy

i was using standard electric bill meter

http://www.airbornegamer.com/wp-content/uploads/2010/04/electric-bill-meter.jpg

but i know for sure that it must be accurate, its the electric company hardware

my rig contains those parts:

MSI 790FX-GD70
SAPPHIRE HD5850 Xtreme
AMD Sempron 140 AM3 BOX
Goodram DDR3 1024MB 1333MHz CL9.0
2 x Fortron FSP650-80EGN
80 GB hdd

A bit more, I have both and recorded down my power consumption at different clocks. But the data's at home so I'll try to remember to share it later if you're interested. I did remember thinking, my rig would be more efficient if my 5870 was a 5850. But then I probably won't have as much performance for my games :D



Quite a few watts, I was surprised to see a significant (>10W can't be sure, again data's at home) difference dropping from 1200Mhz to 300Mhz on my 5870. Not sure if it would make that big a diff by going from 300Mhz to 150Mhz though.

Use a third-party tool, e.g. Sapphire has Trixx if you're using one of their cards.

For now I am running 3 HD 5850 at 1000/350 with a voltage of 1.090V with a corsair 850W Gold

Do you think I can add another 5850 at 1000/350 and 1.090V??

that's because you guys don't take into account power supply efficiency and other hardware like the motherboard and CPU. the DC power draw should be relatively the same, but a PSU with 80+ bronze will suck more juice from the wall than a 80+ gold PSU.

Yes, 1015/300 @ STOCK! (1.085 i believe, not 1.088 as trixx is ALWAYS a few volts UP! Also, fixed fdan needs to be selected on EVERY RELOAD for EVERY CARD! Bug.  A new revision by shapphire xtreme. I posted a info thing but no one see's it in noob section :( Revision is 230SA at the end of the P/N, Not 000SA like most are :) Not volt moddable yet though and ghot a generic answer from shapphire :(

http://forum.bitcoin.org/index.php?topic=29860.msg375290#msg375290

1KW IS PLENTY, JUST MAKE SURE ITS DECENT!!!! END OF :)

I recommend 1000-1200W, because:

it's enough to work with it =/= energy-efficiency

Most PSUs are @ 50% load the most efficient!

no no I am running another Overclocking tool.
I am to 1.090V (I overvolted myself I have BSOD at 1.088 or less)

You are telling me that a 1000W PSU is good but did my 850W gold corsair is enough for my 4 cards?

ps : I will post your thred in the hardware section like this everybody would be able to see it

Can you do that :) thank you :)

Alot of hassle to sim,ply do that, you wouldnt believe. ABuse and all :)

My 850 Watt was cheap and nasty. Struggles with 2x 5850's being OC'd. Good enough for just 2 cards on there own so it shows hopw bad these psu's are :) There £60 :) worth a try i thought :/

I got a 900 Be quiet here i picked up for £100, I think that would be sound for 4 cards but i wouldnt use it as someone said above, running over 90% is bad news in most cases. 80% 1kw is 800W, i wouldnt use any less than 1KW SINGLE psu. I jerry rig mine and use muliple psu's though. its cheaper and spreads p[oer more evenly :)

I run 4x5850@930MHz on a XFX 750W PSU (80+ bronze, draws 850W from the wall.). A friend of mine uses a 650W PSU to power his rig with 4x5850 in it. Doesn't need to be 1200W, that's just overkill IMO.

~20W difference downclocking only memory down to 300Mhz on both my 5870 and 5850

Most PSU are built with some tolerance, especially the lower capacity models in the same series based off the same PCB/design. But it's not ideal to push a PSU constantly at 90% or higher, especially if the ambient temperature is hot due to the cards.

If the PSU dies in a bad way, it can damage connected equipment.

whats a PSU

http://www.google.com :D

You could probably get away with an 850watt, but I would buy at least 1000watt.
You don't want to be running your power supply anywhere near 100%.... it'll just act like a hair dryer and will no doubt have a short life.
 

Bingo. Excellent point. Didn't realize it at the time of my post.

Cheers,
Kermee

What's the breakage on gold vs bronze though? About 5% difference in efficiency?
So for a 800W load

• 85% efficiency = 941W
• 90% efficiency = 889W (delta of 52W)

At 0.15/kwh, this means $0.1872/day in savings for a total of ~$68/year
At 0.10/kwh (average where I live), that means $0.1248/day or ~$46/year

Price difference between Coolermaster 80PLUS Bronze and Gold is about 75, so you break even in over a year or two depending on your power costs. Given that a PSU will last 3-5 years or longer, this is probably a smart investment!

The ABSOLUTE minimum I would go for would be a good single rail 850W. That is with no GPU overclock OR no CPU/MB overclock. 5850's draw roughly no more than 150watts per card really, not clocked. 150W*4=600W, 200W for the other components (unless you have 10x0.8A fans and 10xHDD's, 200W is much for a system - GPU, even overclocked).

If you however want to be safe go for a 1050W PSU (Less likely to hit a bad brand vs 1000W).

Just to add to the PSU wave ~

Get a PSU which is Gold to Bronze certified or whatever it is called. Always read reviews about them. They are advertised with high efficiency, BUT BUT BUT you can advertise with Gold efficiency on a 1000W PSU while meeting the Gold efficiency requirements when the PSU deliver 500W and not at 1000W, and sometimes the other way around!!!

Find 2-3 PSU's you would be willing to get, then reconsider and choose better ones (if money is no hinder), then read the reviews for all 4-6 PSU's to find what fits your purpose the best.

I can also recommend having 2x PSU if your cabinet have the space for it. F.ex. 2 gold efficiency 650W should be cheaper than 1 gold efficiency 1200W PSU, delta temp should be lower (meaning lower temp per PSU, but higher average temp because of 2 units), noise could become higher as dB stack and generally you will have a better (read; more reliable) way of supplying your computer with power.

I'm running 3 x 5850s overclocked, and my entire rig is taking up about 750W, so I would really recommend a 1000W PSU minimum.

Honestly,I don't believe any of the hype in which multiple videocards can work in a system.I have just recently gotten a Radeon 6950 and was trying to get my old 5770 to work in the same system as a seperate videocard but it never wanted to boot whenever I tested the system.I have a TX650W Corsair PSU which didn't seem to like the fact of both videocards being in the system and had to take it out as I thought the power requirements wouldn't be that high for both cards.

I would recommend getting at least a 1000 watt PSU to be on the safe side as it may also have more PCI-E 6 pin connectors for multiple GPU combinations.

That's not how the 80+ certification works. In order to get a real 80+ certification, the PSU must pass efficiency tests at 20%, 50% (high efficiency is required at this load) and 100% load. If a PSU advertises gold efficiency only at one load level, it's a fake certification. There are some brands that had advertised and put the 80+ logo on PSU that were NEVER actually certified because they know it sells better.

To verify the model you are looking at is really certified, check out the certification website
http://www.plugloadsolutions.com/80PlusPowerSupplies.aspx

It could just be the motherboard not being happy with two cards. Have you tried different slots and different slot order? How old is the TX650 anyway? PSU capacity will degrade over time, faster if the environment is hotter.

1000W would be safe with some headroom, better safe then sorry if its a lower quality PSU and can't generate 1000W reliably after year+ of dedicated mining.

Yes, what you are saying is right, in theory. However, if you test them in practice some will actually not meet the said ceritification. F.ex the in-win 1200W psu have a slight problem at full load not delivering more than 78-79% efficiency (Add to that it has problem even delivering 1200Watts...). Might be the certification, might be a bit faulty parts here and there, but the fact is that in real use they do not deliver advertised 80+ standards. Now that might not be a problem at all for some, but to me it's a red flag for build quality and reliability.

Quite a few of them have similar problems actually. However for most users, checking up the 80+ list is the first step. If it's not even there, then obviously it's not even going to cut it. After that, it's quite difficult to determine which are consistently good and which are not. Which was why in one of my previous jobs, I was in charge of testing various PSU before committing the company to buying one or the other. Wish bitcoin existed then, I could had figured out a way to convince them to use computers instead of load testers and mined quite a few BTC while doing that job :D

There was at least one very well known manufacturer which had PSU that did not pass muster to my surprise then. So keep in mind that just because a site says a PSU is good, doesn't exclude the possibility that it was a golden sample, or in some cases I had another reputable manufacturer switching to cheaper parts on products (not a PSU) and a not so reputable one doing the same for PSU after the first few excellent batches.

However despite all these, just because a review site (or end user testing) claims that a particular PSU does not meet 80+ standard does not mean the PSU isn't designed and manufactured up to the certified standard. IIRC 80+ tests PSU in very strict environmental conditions, which does not match most review sites conditions. E.g. environment temperature controlled at 25C. Due to thermal derating (manufacturers will provide a chart for their products if you have good reasons to ask), the way most sites test PSU by putting it in a realistically hot environment will decrease the max load and efficiency of the PSU.

Furthermore, 80+ also calculates wire losses in their certification. So modular PSU as well as longer cables means the calculated efficiency is higher than measured. Although this should be a less than 1% difference.

So the only thing the review sites can tell you is at best the relative performance of PSU to one another on their test system using their methodologies. For most of us, it would be too much time spent just to read up on every available PSU, compare between them for each site to come up with the best buy.

So easiest way is still to refer to the 80+ chart, take a quick look at what people are using here without problems and ignore whatever 1~2% difference things might make. It'd probably be made up by the BTC you could mine while doing all that research :D

So is 700w good enuff for 2x5830 and a 5770

Depends on which 700W PSU it is ;)

Cheers,
Kermee

Its this one http://www.newegg.com/Product/Product.aspx?Item=N82E16817182191 (http://www.newegg.com/Product/Product.aspx?Item=N82E16817182191)
Thx

In theory, that should handle 2x5830 and 1x5770... *Maybe* even another 5830 (but won't leave much headroom), depending on which MB/CPU you're using.

But 99% sure you're fine, even if you OC the 5830's and 5770's.

Cheers,
Kermee

Sweet thx bud