High Rated PSUs Unnecessary

[Zap]

Had a good 520W Enhance w/80+ bronze, originally running an OC'd Core2 E8400 and OC'd Radeon 4850, no problem. Replaced the CPU and GPU with an i5 3570K and MSI GTX 460 Hawx, and while I was fine at stock, when both were OC'd, my system would shut off during intense gaming sessions.

I think that was a problem with the OCP on certain older Enhance units. I had a 500W Enhance that couldn't run my Core 2 Duo with GTX 285 (system would suddenly power off), but a 430W Antec True Power Trio ran it just fine. The Enhance had the OCP set pretty low on each of its dual rails, while the Antec was a single rail Seasonic unit. This was made in the early days of multi rail PSUs, before manufacturers figured that stuff out.

 

[philipma1957]

i wouldnt want to see my power bill after running a bitcoin machine 24/7 thats drawing 1100w!

yeah if you pay 16 cents for a k watt of power like I do underclocking is better then overclocking. comes to less then 16 cents when you figure in the heating savings in cold weather.

I can run 3x 7970's at 1600 hash underclocked and pull 490 to 520 watts.


If I overclock to 2000 hash .

I will pull 900 watts.

so the last 400 hash cost me 1 watt per hash!

while the first 1600 hash cost me about 1 watt for 3 hash!

 

[JEDIYoda]

Your English is fine. If you want to magically sound very intelligent, start posting in Off Topic.

Now that is funny!!! Could have added P&N to that also..lololol

 

[Evadman]

I run 8 gpus in 3 systems pulling about 1400 watts my 3 psu's are rated at 2360 watts. all is on a 20 amp circuit breaker and the interior wire is 10 ga not 12 gauge.

The max sustained you can pull out of a 20 amp 120v circuit is 1920 watts before the breaker will start tripping due to overload. (80% sustained is what they are supposed to be set at). You have 400 watts there that you can't use.

Also, you should switch to 240v because you will save 4 to 6% in efficiency. Since you are using 1.4kwh per hour on a 365/24 operation, switching to 240v will save you (1.4*365*24* 11 cents per kwh * 5%) = $108 per year. That's like an extra 15 bitcoins :whiste:

 

[tcsenter]

Just don't go to MSI User Forums and seek help for any problem if you don't have a $80+ 600W+ PSU. No matter what the symptoms of your problem are, no matter if you even have a high-end graphics card, they will insist your PSU is inadequate and recommend something grossly unnecessary. After you go buy some overpriced/overpowered unit and it does NOT solve anything, their response will be "well now at least you have a good PSU" as though you should be thanking them for causing you to incur an unnecessary expense for nothing.

I'm not kidding. I got banned (for a month) for debunking or being critical of such nonsense.

 

[pandemonium]

I had no idea this was specifically regarding graphics card manufacturers and their slanderous marketing of power requirements.

My points were simply in addition to. Hence why I said so in the first 4 words.

I find it interesting that I bring up devil's advocate pointers and get slammed as being a marketing proprieter, lol. Perhaps you two need to read my sig and the thread within. Your assumptions will be dismayed...

Yeah? FYI....they all are. And this has no bearing upon why gpu manufacturers overestimate "recommended minimum" wattages from power supplies. Rather, as was stated previously, it's much more about cheap junk in people's computers----like Deer, Allied, Diablotek---that pass themselves off as being to output XXX watts from the unit while in reality can only deliver half rated output on the +12V rail.

Actually I disagree that you generalizing things from an engineering standpoint; I could imagine you designing a product that would be running DV failures left and right even if the system was actually fine, because what was REQUIRED to be met simply isn't paired appropriately with the intended use of the system.

I would say that your requirement should be the minimum of what you need - i.e. a REQUIREMENT that is going to act as a constrain on the design.

The actual specification/implementation that is selected can be overkill relative to the requirement (considering factors like time to implement, cost, complexity, etc etc)

That way you can pass your requirement, which is based on the reality of what is needed, and your actual design exceeds that requirement by quite a bit.

Videocard manufacturers pushing ridiculous 'Requirements' (ie: these are not engineering requirements in the same fashion) are responding to factors outside their control: i.e. the power supply. And this response, while being engineering in nature, is being driven much more from the marketing/legal position.

 

[Tsavo]

Decent watt ratings on high-quality PSU's are like guns, condoms and chewing gum; it's better to have them and not need them than need them and not have them.

And besides, excellent PSU's are cheap these days. I bought a stack of Antec branded Seasonic 620's for $35 each.

 

[Deders]

i have also found that people very much enjoy gaming in over heated rooms and paying a lot of money on their power bills, just as long as they can say "hell yeah, i have a 1000w power supply in my computer!"

Not that the 1000W PSU is going to heat their rooms any more than a good 500W, but if running boinc or folding costs less to heat a room than an electric heater (we have no central heating) then I'm game!

 

[Lonyo]

Not that the 1000W PSU is going to heat their rooms any more than a good 500W, but if running boinc or folding costs less to heat a room than an electric heater (we have no central heating) then I'm game!

It will, only marginally, but it will, since the 1000w will almost be guaranteed to be less efficient at the loads the 500w can handle than the 1000w, even if they have the same rating (e.g. Platinum).
But only a handful of watts at most.

 

[VirtualLarry]

Not that the 1000W PSU is going to heat their rooms any more than a good 500W, but if running boinc or folding costs less to heat a room than an electric heater (we have no central heating) then I'm game!

Electric heaters are basically 100% efficient. So it would cost the same to heat with BOINC than with an electric heater. So might as well build that uber-DC rig for wintertime!

 

[philipma1957]

The max sustained you can pull out of a 20 amp 120v circuit is 1920 watts before the breaker will start tripping due to overload. (80% sustained is what they are supposed to be set at). You have 400 watts there that you can't use.

Also, you should switch to 240v because you will save 4 to 6% in efficiency. Since you are using 1.4kwh per hour on a 365/24 operation, switching to 240v will save you (1.4*365*24* 11 cents per kwh * 5%) = $108 per year. That's like an extra 15 bitcoins :whiste:

You know I am running this in a spot that I could access my 240 line used for my central ac. My psu's are all seasonic. they allow 240 volts.

it also lets me add more units since my 240 line is 35 amps 35 amps at 240 is more then 6000 watts even with the 20% sustained. 35 x 240 x .8 = 6720.

I could add 10 more gpus! easy!

As a NJ home owner I am allowed to wire my own home with a permit and Inspection.

 

[Red Squirrel]

I've actually considered running 240v for all my server stuff. It would probably be slightly more efficient.

Makes things more complicated when it comes to UPS backup though. While they do make 240v 60hz inverter-chargers they are much harder to find than 120v 60hz ones. In fact even those arn't as easy to find in sine wave or psudo sine wave (as opposed to square wave)

 

[philipma1957]

this would be an easy call if butterfly labs went bankrupt. I would grab more gpus and mine away. at least until Apr

 

[NeoPTLD]

Also, you should switch to 240v because you will save 4 to 6% in efficiency. Since you are using 1.4kwh per hour on a 365/24 operation, switching to 240v will save you (1.4*365*24* 11 cents per kwh * 5%) = $108 per year. That's like an extra 15 bitcoins :whiste:

Not necessarily. You'd have to obtain an accurate data on load vs efficiency chart for the power supply and compare the graphs at 120 vs 240v.

The best approach is to go with 80Plus Platinum power supply and sign up for time-of-use plan and schedule the computers to only crunch during off-peak and ideally computer can operate with just natural ventilation even on the hottest days. Natural cooling is the new trend in data centers as load on A/C is the major power cost.

My PoCo's rate during 10PM to 6AM period and Sundays is about third that of peak rate. Something like 5c/kWh + distribution fees. Make sure to use in non A/C'ed space and vent outside, so you're not causing cooling demand.

You should probably notify your power company with explanation of what you intend on doing though, so they don't call the police suspecting you started a grow-op.

 

[Deders]

Electric heaters are basically 100% efficient. So it would cost the same to heat with BOINC than with an electric heater. So might as well build that uber-DC rig for wintertime!

Surely 500W at just over 1amp will cost a lot less than 500W at 9-10amps?

 

[yepp]

I think that was a problem with the OCP on certain older Enhance units. I had a 500W Enhance that couldn't run my Core 2 Duo with GTX 285 (system would suddenly power off), but a 430W Antec True Power Trio ran it just fine. The Enhance had the OCP set pretty low on each of its dual rails, while the Antec was a single rail Seasonic unit. This was made in the early days of multi rail PSUs, before manufacturers figured that stuff out.

This is also true for my 6 year old 550W Antec NeoHE(which is still going strong). Due to the shoddy design of how the three 12v rails are distributed the OCP would trigger during heavy gaming with an OC'd Q6600 and GTX 260. One 18A 12v rail is dedicated to the modular cables where the OCP was being triggered, the other two 12v rails powers the CPU and motherboard. So had to remove a DVD drive and have one of the fans powered via the motherboard, been running fine ever since.

 

[BFG10K]

The early multi-rail PSUs had issues because of badly designed rail distribution and/or incorrectly set OCP values. A modern multi-rail PSU (e.g. Enermax units) is just as capable as a single rail PSU at the same wattage.

Also modern OCP trip points are generally much higher than the label reads, so there’s plenty of reserve before even an overloaded rail would trip. They’re usually set to less than 55A though, so they’re still quite safe.

 

[VirtualLarry]

Surely 500W at just over 1amp will cost a lot less than 500W at 9-10amps?

500W is 500W dude.

 

[NeoPTLD]

You know I am running this in a spot that I could access my 240 line used for my central ac. My psu's are all seasonic. they allow 240 volts.

it also lets me add more units since my 240 line is 35 amps 35 amps at 240 is more then 6000 watts even with the 20% sustained. 35 x 240 x .8 = 6720.

I could add 10 more gpus! easy!

As a NJ home owner I am allowed to wire my own home with a permit and Inspection.

Even if you're using just 5kW around the clock for a month, you'll be at 3,600kWh. That's police notification level usage not to mention $400-500/mo power bill at 12c/kWh rate after all distribution fees, transmission fee, etc have been added.

 

[GotNoRice]

I don't see how large power-supplies are a "scam".

It comes down to knowing how big of a PSU you will need and making an appropriate purchase.

Large PSUs would only be a "scam" if there were never any real situations where they were actually useful. In fact, it's rather easy to push a 1000w PSU to it's limits if your components are power hungry enough.

I originally bought my 1000w PSU because I was running 2x 4870x2 in my main computer.

Never felt scammed.

 

[UaVaj]

rated watt and actual watt are two different numbers.
then comes voltage drop and ripples.



"never felt scammed" X2

the reality check is. just spent $900 on a pair of 7970 not to mention the rest rest of the system. $100 for a seasonic XFX 850 XXX (~950w clean power tested) to power all those expensive equipment is cheap in comparison.

if you are even cheaper. get a superflower NXZT HALE90 1000w on ebay. buy now for $80 shipped to your door. slightly more ripples but well within spec.

 

[jacktesterson]

I've had a 2500k @ 4.5 GHz and 2 x 7850's at 1150/1325 running off a 550w OCZ ZT Power Supply (45a) without issue for 3-4 weeks of playing around.

Currently only running one 7850.

I don't think High rated power supplies are a "scam". Components are obviously becoming more efficient.

I also think component makers often over state required Power requirements simply to protect themselves. Makes sense.

 

[riva2model64]

And that's part of the issue. How do they know what I have in the rest of the system or if I already compensated for it? The numbers are greatly exaggerated especially when you have multiple cards. I did not know this when I bought my video cards and I was almost wondering if even 1000w would be enough but it turned out to be more than enough.

You don't see a 100w light bulb say it requires 400w because it assumes the fixture has 3 more sockets.

The manufacturers DON'T know what else you have in the system, and thus they have give an overestimate. If they said you needed a 200w PSU but you had a High TDP Quad-core and a few hard drives, you would be screwed (even if it would work fine with a dual-core). In the fine text, it usually says something like "atleast 400w for typical system but unusual circumstances may require more." They also have to add some wattage due to varying quality of power supplies.

I agree that It would be simpler if they just posted the actual max power draw of the video card on the box, but this would probably confuse the average buyer. A quick google can usually reveal the power draw a particular video card so you can balance your power needs.

 

[philipma1957]

Even if you're using just 5kW around the clock for a month, you'll be at 3,600kWh. That's police notification level usage not to mention $400-500/mo power bill at 12c/kWh rate after all distribution fees, transmission fee, etc have been added.

police are always welcome in my home. I don't smoke it any more. You know I had a 480 watt sunlight lamp setup in my home in 2005. I ran it in my garage for 16 hours a day from oct 1 to may 15th. Cops paid a visit so I showed them what i was growing a fig tree. Very long story as to why but the cops and I had a good laugh.

 

[jacktesterson]

My power bill is $500 a month in the winter. I'm in Canada though