Earthwatts 650, how can I find my maximum?

I have an Antec Earthwatts 650, and it's been a good powersupply for me but I can only really guess as to if it's being overtaxed or not.

I know that from most other people I see running this powersupply I seem to have more on mine than almost all of them.

There are two main issues I'm concerned with. I can hit 4.5Ghz with my Q9650 but it is not Prime stable and also crashes within the first 30 seconds or so of Vantage. I know that quads suck a ton of juice and the usage goes up quite a bit the higher you overclock. I don't really know if my OC is being held back by my PSU or not.

The 2nd issue is that I'd like to upgrade to a 5870 soon. I don't really know what the difference in power consumption would be between two 4850's and a 5870, but I don't want to get myself in a situation where I have a 5870 in hand but my system won't boot because it doesn't have enough power.

I do have a bit of wiggle room in that I could probably move a bunch of my hard drives over to my server and access them over the network or just get external usb enclosures for them, but I'm also not sure if removing hard drives would really take any strain off since they are on different rails.

Any tips?

Two 4850's consume about 220w combined, a 5870 consumes 190w. You're fine there.
I doubt you're capped it out, you get 540 watts to play with, the CPU isn't going to be over 150, and the GPU like i said will be 200ish. That's 350 which leaves 190 for drives and such.
I wouldn't add a second 5870, but aside from that you're fine.

They sell power meters that plug into the wall (like an adapter between your PS and wall outlet). Multiply the reading by the efficiency of your PS, and you get the power consumption of your computer.

GotNoRice said:

There are two main issues I'm concerned with. I can hit 4.5Ghz with my Q9650 but it is not Prime stable and also crashes within the first 30 seconds or so of Vantage... I don't really know if my OC is being held back by my PSU or not.

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Wow, your overclock is probably higher than what most people can get, and you don't think that perhaps you are reaching the limitations of your chip?

What are your temperatures and voltages at those clocks? What clocks are you stable at? I've noticed that CPUs tend to tell us when they've had enough, because at some point they start needing a LOT more voltage to go a bit higher.

Bobnova said:

Two 4850's consume about 220w combined, a 5870 consumes 190w. You're fine there.
I doubt you're capped it out, you get 540 watts to play with, the CPU isn't going to be over 150, and the GPU like i said will be 200ish. That's 350 which leaves 190 for drives and such.
I wouldn't add a second 5870, but aside from that you're fine.

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ehhh that CPU can easily push 150W... especially at the clocks hes running it at....

Aside from that, I will concur. That PSU should be fine for any single card + quad core cpu.

As far as his overclocks, hes probably hitting the FSB limit on that board or chip. There are only a handful of of boards that can push 500FSB stable, P5Q-pro can if it has a modded bios flashed to it....

cyberfish said:

They sell power meters that plug into the wall (like an adapter between your PS and wall outlet). Multiply the reading by the efficiency of your PS, and you get the power consumption of your computer.

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Yeah I have a kill-a-watt. From what I've read lately though people seem to think they are wildly inaccurate due to PFC or w/e. I might break it out anyway and see what it says.

Zap said:

Wow, your overclock is probably higher than what most people can get, and you don't think that perhaps you are reaching the limitations of your chip?

What are your temperatures and voltages at those clocks? What clocks are you stable at? I've noticed that CPUs tend to tell us when they've had enough, because at some point they start needing a LOT more voltage to go a bit higher.

Click to expand...

Yeah it's certainly possible that I've hit the limits of my chip. There are a few things that make me wonder however. When I was upgrading my friend's rig to i7, he had an Antec Neopower 650w. I believe that powersupply is equal or better than my Earthwatts 650. We ended up getting an Antec Quattro 850 and that made the difference in being able to clock his i7 past 4Ghz. Also looking at a semi-old anandtech review where they look at the power consumption of a QX9650 (should be similar enough to my Q9650) the power consumption appears to increase exponentially past 4Ghz:

http://www.anandtech.com/cpuchipsets/intel/showdoc.aspx?i=3184&p=2

I run at 1.4v with LLC enabled. I am stable at 4.4Ghz. Prime95 temperatures peak at 85C which I acknowledge is extremely hot however it was still stable and the main game I play (World of Warcraft) has the CPU running at about ~67C while in-game. All temperatures measured with Coretemp.

I am considering re-seating my Tuniq Tower and I also want to swap out the stock fan for one of these: http://www.newegg.com/Product/Product.aspx?Item=N82E16835213006 150CFM through the heatsink should bring temps down a bit, but if power is my issue adding a fan that sucks almost 2 amps from the 12v rail is probably the last thing I need.

Here are my Kill-a-watt measurements:

Idle at Windows 7 Desktop (Aero Enabled): 264watts
Prime95 Torture Test Small-FFTs: 475watts
Furmark (Both GPU's loaded, one CPU core loaded): 498watts
Prime95 Torture Test Small-FFTs (enabled on 3 cores) + Furmark (2 GPU's, 1 core loaded): 650watts

The hard drives are somewhat of an unknown variable, and the PPU is as well.

It looks like you ARE pushing the limits of the 650W PS.

GotNoRice said:

Here are my Kill-a-watt measurements:

Idle at Windows 7 Desktop (Aero Enabled): 264watts
Prime95 Torture Test Small-FFTs: 475watts
Furmark (Both GPU's loaded, one CPU core loaded): 498watts
Prime95 Torture Test Small-FFTs (enabled on 3 cores) + Furmark (2 GPU's, 1 core loaded): 650watts

The hard drives are somewhat of an unknown variable, and the PPU is as well.

Click to expand...

Now take into account that the KaW is not accurate and the fact you need to subtract 20% off that value for PSU efficiency.......

I didnt see you were running Crossfire 4850's... I would step it up to the same wattage, maybe a bit more, but a better brand.

Wooha, that's some juice right there.
That an active PFC PSU? They screw with kill-a-watt meters from what i've read.

Antec has a pretty good source for determining power requirements - here:
http://www.antec.outervision.com/

Thats the same calc as the original Extreme outervision calc in which he paid $1.99 for (though it works just fine free). Antec licensed that to use with their site.

http://extreme.outervision.com/psucalculatorlite.jsp

The "Overclock my cpu" thing is out to lunch, at least where PhII cpus are concerned.

Bobnova said:

The "Overclock my cpu" thing is out to lunch, at least where PhII cpus are concerned.

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Looks about right to me... 190W with PhII X4 955 at 4Ghz with 1.5v from 1.35 stock.

EarthDog said:

Thats the same calc as the original Extreme outervision calc in which he paid $1.99 for (though it works just fine free). Antec licensed that to use with their site.

http://extreme.outervision.com/psucalculatorlite.jsp

Click to expand...

Ohh, didn't know that..

GotNoRice said:

Yeah I have a kill-a-watt. From what I've read lately though people seem to think they are wildly inaccurate due to PFC or w/e. I might break it out anyway and see what it says.

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Actually, they are not inaccurate at all. My father-in-law is an electrical engineer and tested this against very heavily calibrated equipment. The sample I got from Newegg was within 2-3% margin of error, which is amazing for a consumer-level, very inexpensive device.

EDIT - Here's a nice post @ Johnny Guru testing their accuracy as well with the same type of load an Active PFC PSU would give. There is one naysayer in there as well, his reading was 4% off in the photo he posted. Still very, very good for a $20 piece of equipment. FWIW.

Clock speed makes little difference in wattage consumed on a Phenom II (look for an article from me on that, coming soon ), a 25% OC from 2.6 to 3250 with no voltage gains raises wattage by 9% or less.

Yep, thats common knowledge!! ^^ (but who were you talking to?)

Hokie, let me link you to a thread I started a bit ago on this subject...
http://www.ocforums.com/showthread.php?t=595686

I ust noticed it has Spectre in there as well, the same 'naysayer'. But between him and OW............those are two of the best we have around us, yes?

Their calculator doubles wattage if you double speed. 25% more speed = 25% more wattage on the calculator.

20% is what I am seeing without a voltage change (for 25% o/c's) for both Intel and AMD... How did you test your load increase? (I really want to see this article now!)