600W or more, why do I need it?

[ksquared]

Everybody is saying get the gigantic power supply. But my calculations from http://www.extreme.outervision.com/PSUEngine say I only need 329W to power the system.

Asus says 600W "for a fully configured system." The motherboard can have at least 6 or 8 hard drives, which all take the power, while I would be using 3, along with a bunch of other things I probably won't be using, such as an optical drive. I am looking at the 65W CPU to save a bit of power there, which Asus might not have counted on.

The 350W PSU should be even more efficient since it would be running closer to capacity. I know that at startup there is an initial surge, but is that the only real reason to have the 600W supply? I thought it was possible to delay the hard drive starting for a second or two so that the surge wouldn't be as great.

And what about the Thermaltake 250W PSU in the 5.25 drive slot? Would that solve all the problems or is it not really necessary?

[nvidiaOCmaster]

600W is plenty m8.

[ksquared]

That's what I was figuring too. So is it possible that the 350W supply will be able to supply enough power?

[Soichiro]

Asus probably assumes people will go find the cheapest PSU they can find. Well, a 600W Powmax will only support about 300W in reality before it explodes. If you actually get a decent power supply, 400W should be more than enough if you're not OC'ing.

[nvidiaOCmaster]

Yea, trust me, you don't want to cheap out on your power unit.

[funnyperson1]

I wouldn't use a 350W PSU to run a machine that maxes out at like 300-350W, because the PSU will be under stress all the time. Not to mention that most poor quality PSUs can't ouput anywhere near the rated numbers anyway. The other problem is that 329W is distributed among the various rails and a lot of great 350W psus that rocked PIIIs and AXPs, simply cannot put out enough current on the 12V rails for a modern system.

For your kind of system I would get a good quality 500W power supply, you could get something like the XClio Goodpower 500 for $50, or a Sparkle/FSP for around the same price. For a little more ($70 or so) you can get an Enhance 5150gh which is also extremely efficient and will save you money on your power bill over time. Also the higher wattage allows you room to upgrade.

[Moto7451]

Also one good PSU is more likely to last you longer than several cheapies. if you have to go from 350 to 400 to 500 watt PSUs over the span of a few years you may as well have just purchased a quality 500-700W unit instead.

[ksquared]

I do agree with Moto7451 about how it is better to get the right power supply the first time.

But I don't think that a powersupply that is called on to deliver the power it is rated for should die a premature death because of stress. However, if that is true, it would explain why people are getting the 600W power supplies when I'm calculating 330W. And I found out that calculation was mistakenly calculated with SLI, but I'm starting out with just a single video card so it calculates at 275W then. Also, for the Phantom 350 it is rated at the highest efficiency (85%) at full load.

So the current plan is to keep using the Antec Phantom 350 and see what happens. I guess I can always get a bigger power supply if I have to.

[funnyperson1]

There is no doubt that most people overcompensate the PSU they need. The overstressing part normally occurs with lower quality PSUs. You are right that a power supply should output the wattage that it is rated for, the problem is that a lot of them don't, or that they will with major ripple, or they will, but will fail a lot sooner.

Antec in particular with their Channelwell built units have a notorious reputation for having cheap capacitors that blow up when subjected to heat. Of course, the higher the load on the PSU, the more heat it creates.

Now I am pretty sure that your Antec is not made by Channellwell, and doesn't have the cheap Fuhjiyyu capacitors in it (it would be suicide to put those in a passive psu). It also has a 12V1 rail with 18A which should be enough for all but the most hungry video cards. Also, that efficiciency if freaking impressive.

[mantralord]

There is no doubt that most people overcompensate the PSU they need. The overstressing part normally occurs with lower quality PSUs. You are right that a power supply should output the wattage that it is rated for, the problem is that a lot of them don't, or that they will with major ripple, or they will, but will fail a lot sooner.

Antec in particular with their Channelwell built units have a notorious reputation for having cheap capacitors that blow up when subjected to heat. Of course, the higher the load on the PSU, the more heat it creates.

Now I am pretty sure that your Antec is not made by Channellwell, and doesn't have the cheap Fuhjiyyu capacitors in it (it would be suicide to put those in a passive psu). It also has a 12V1 rail with 18A which should be enough for all but the most hungry video cards. Also, that efficiciency if freaking impressive.

Yes, it is a huge misconception that a power supply running near its peak is somehow struggling and will soon die. This is only true for lower quality units, which almost nobody who spends more than $50 on a PSU will have to worry about anyway (unless it's an Antec or an Aspire/Apevia).

[funnyperson1]

I take back what I said about the Phantom not having the cheap capacitors. Looking at the SPCR review it does look like Fuhjiyyu caps (shudder) inside.

http://www.silentpcreview.com/article188-page2.html

[Valk]

a 400 watt dualrail fsp/spi will do you just fine. Cant run sli with that, but if you have one decent graphics card, 2 or 3 harddrives and a optical it will handle it without issue. The only reason i upgraded mine was to keep the 12v a little more stable when overclocking on my dfi, otherwise, that $40 unit was as good as my $150 ocz.
You certainly dont HAVE to be spendy. but 400 watts would be about the minimum for a modern systemi would say, to keep a safe, steady stream of power. The closer you get to the theoretical maximum of the psu, the less stable the power becomes.

[Adragontattoo]

You don't NEED a 600w PSU, I know I didn't when I built my main rig last year. I did get a 600w though, just for a bit of future proofing. I am running SLI but the cards only pull power off the PCI-e slot and don't need to be plugged in to the PSU as well. If I end up upgrading to a 7900 g(something) then I will need more of the PSU then I do now. Also if I end up having to move data around I can drop drives in without worrying about the PSU.

I try to build with the knowledge that I WILL have this rig for awhile and so I accommodate as needed.

[Joeteck]

a 400 watt dualrail fsp/spi will do you just fine. Cant run sli with that, but if you have one decent graphics card, 2 or 3 harddrives and a optical it will handle it without issue. The only reason i upgraded mine was to keep the 12v a little more stable when overclocking on my dfi, otherwise, that $40 unit was as good as my $150 ocz.
You certainly dont HAVE to be spendy. but 400 watts would be about the minimum for a modern systemi would say, to keep a safe, steady stream of power. The closer you get to the theoretical maximum of the psu, the less stable the power becomes.


IMO, I would stay away from dual rail power supplies. They have separate outputs, and you will over load much easier.

One output is for the CPU, and the other is for all your other hardware. Keeping everything on one rail will not limit your upgrade path. Again my opinion.

EDIT:

This is a decent 430 watt (http://www.newegg.com/Product/Product.asp?Item=N82E16817153023) power supply

This one (http://www.newegg.com/Product/Product.asp?Item=N82E16817703005) is better.

Personally, I would get get the best you can afford so you'll never have to worry about it again. EVER!

EDIT #2: That power supply calulator said I needed a 395Watt PS.

[mantralord]

Personally, I would get get the best you can afford so you'll never have to worry about it again. EVER!

No PSU will last forever because Intel changes the ATX standards all the time, so even if a PSU has enough power, it might not be physically compatible with stuff down the road. This is exactly why nobody should buy much more power than they need.

[Joeteck]

No PSU will last forever because Intel changes the ATX standards all the time, so even if a PSU has enough power, it might not be physically compatible with stuff down the road. This is exactly why nobody should buy much more power than they need.


IMO, Thats bad advice.

Plus you're assuming that intel will change. In all the years you've been doing PC's how many time has the power supply changed?

Never!

Still, 3.3, 5v. +12.

By the time they make any changes, you would have upgraded at least 10 times and still using the same beefy power supply..

[mantralord]

IMO, Thats bad advice.

Plus you're assuming that intel will change. In all the years you've been doing PC's how many time has the power supply changed?

Never!

Still, 3.3, 5v. +12.

By the time they make any changes, you would have upgraded at least 10 times and still using the same beefy power supply..

I'm talking about the physical connections. In the past 6 years, they've introduced the P4 connector, the EPS12V connector, 24-pin ATX connections, SATA connectors, PCI-E connectors, and now 8 pin PCI-E connectors.

[Adragontattoo]

I'm talking about the physical connections. In the past 6 years, they've introduced the P4 connector, the EPS12V connector, 24-pin ATX connections, SATA connectors, PCI-E connectors, and now 8 pin PCI-E connectors.

If your main rig is 6 years old then the least of your worries is about current connections and what might be upcoming.

[smokie mcpott]

dont forget about 8-pin cpu also

[Rattle]

i think thats the eps12v connector he listed

[Joeteck]

I'm talking about the physical connections. In the past 6 years, they've introduced the P4 connector, the EPS12V connector, 24-pin ATX connections, SATA connectors, PCI-E connectors, and now 8 pin PCI-E connectors.

Ok, how many video card and mother board manufactures provide you converters for such changes? EVERY ONE OF THEM...

I would buy the biggest and the baddest Power supply you can afford.

One of the most common mistakes people make is buying low end / or low quality power supply. And wonder why their $50 PS just took out their 8800GTX.

Please don't fall into this category and become a statistic.

[Adragontattoo]

IMO, Thats bad advice.

Plus you're assuming that intel will change. In all the years you've been doing PC's how many time has the power supply changed?

Never!

Still, 3.3, 5v. +12.

By the time they make any changes, you would have upgraded at least 10 times and still using the same beefy power supply..

Not quite true. Your old PSU that was meant for a heavy 5v load wont work too well with the newer 12v reqs. SN, OK wolf or JohnnyG can tell you more about that then I can.

[mantralord]

Ok, how many video card and mother board manufactures provide you converters for such changes? EVERY ONE OF THEM...

I would buy the biggest and the baddest Power supply you can afford.

One of the most common mistakes people make is buying low end / or low quality power supply. And wonder why their $50 PS just took out their 8800GTS.

Don't fall into this category.

I agree that people should buy a quality unit, but not the most they can afford. They should buy based on the kind of hardware they'll be running for at most 3 years into the future. Someone who buys a 1KW instead of a quality 500-600W for their machine is really just doing it out of ignorance or ePenis. Also, when the 1KW becomes obsolete, it'll be be resold, and perhaps 10 years down the line end up at a landfill somewhere where it'll leak all the dangerous chemicals used to make it. A nice ROHS-compliant PSU like the Enhance 500W is better for the environment, which is a good thing.

[Rattle]

i try and make it so when I build a new machine, I can built my next one with the same psu, anyone that thinks you can do better than that is fooling themselves. new plugs and power requirments will decide that for you, not me or you.

[Joeteck]

Not quite true. Your old PSU that was meant for a heavy 5v load wont work too well with the newer 12v reqs. SN, OK wolf or JohnnyG can tell you more about that then I can.


Lets talk about the same thing shall we?

The requirements have changed, not the PS.

Also, thats a real good point I want to address.

Speaking of which if you had a so called 600W PS, how much is on the 12v rail?

If you notice, the 3.3v and 5v rails are still very high in terms of output.

Some have a 40A 5v Rail, and these guys know about the new requirements. They just want to give you false hope about their PS so called 600Watter.

3.3v does not need to be any thing more than 10amps, the 5v rails does not need to anything more than 15amps...

But good Power supplies are 24 and 30 respectfully.

[Adragontattoo]

I have quite a few rigs that NEED the 5v heavy PSUs. Luckily I can still get them.

Not that I really need 2 PC&C 510's or a Zippy 500 or 2 Emacs 300w or the FSP 600w and FSP 500w but I have them all, and use every one of them except a single PC&C 510 that is waiting for a decision.

[Joeteck]

I agree that people should buy a quality unit, but not the most they can afford. They should buy based on the kind of hardware they'll be running for at most 3 years into the future. Someone who buys a 1KW instead of a quality 500-600W for their machine is really just doing it out of ignorance or ePenis. Also, when the 1KW becomes obsolete, it'll be be resold, and perhaps 10 years down the line end up at a landfill somewhere where it'll leak all the dangerous chemicals used to make it. A nice ROHS-compliant PSU like the Enhance 500W is better for the environment, which is a good thing.

Not really. How many power supplies have you bought in your lifetime? Add it all up. Mean while I just bought one, and enjoying my investment. ;)

[Joeteck]

I have quite a few rigs that NEED the 5v heavy PSUs. Luckily I can still get them.

Not that I really need 2 PC&C 510's or a Zippy 500 or 2 Emacs 300w or the FSP 600w and FSP 500w but I have them all, and use every one of them except a single PC&C 510 that is waiting for a decision.

Want to sell the 510? Just kidding... I have a 750 Quad waiting to be used...

[Adragontattoo]

sure we can trade 510 for the 750!, wait why am I banned AHHHH NOOOOOOOOO!!!!!!!

[Super Nade]

Everybody is saying get the gigantic power supply.

You only need to get a unit which would suite your load. No need to get a humongous 10 TW unit for a 500W load. ;)

[Goshawk]

Don't forget that a power supplies output changes drastically when there are temp ambient changes.

As a power supply gets hotter, the less efficient is gets and thus peak output declines. Also, amperage is very important to look at too as was stated previously by others in the thread as well.


~ Gos

[funnyperson1]

IMO, I would stay away from dual rail power supplies. They have separate outputs, and you will over load much easier.

One output is for the CPU, and the other is for all your other hardware. Keeping everything on one rail will not limit your upgrade path. Again my opinion.

EDIT:

This is a decent 430 watt (http://www.newegg.com/Product/Product.asp?Item=N82E16817153023) power supply

This one (http://www.newegg.com/Product/Product.asp?Item=N82E16817703005) is better.

Personally, I would get get the best you can afford so you'll never have to worry about it again. EVER!

EDIT #2: That power supply calulator said I needed a 395Watt PS.


You tell people to avoid dual-rail PSUs because they only put out 18A on each rail, and then you suggest a single rail PSU that only puts out 18A on the 12V? Where is the logic here?

Single rail psus are only better than dual rail ones when the single rail can actually put out more than one rail of the dual-rail psus.

If you wanted a cheap PSU on a new 12V heavy system, go for this one:
http://www.newegg.com/Product/Product.asp?Item=N82E16817104953
Or this one:
http://www.newegg.com/Product/Product.asp?Item=N82E16817189003

Both can put out about as much current on a single 12V rail as that TT PSU and still have an extra rail that can put out 15+ amps. In any case the PCIE connector will be on a different rail and ultimately you have far more usable power.

[ksquared]

Don't forget that a power supplies output changes drastically when there are temp ambient changes.

As a power supply gets hotter, the less efficient is gets and thus peak output declines. Also, amperage is very important to look at too as was stated previously by others in the thread as well.


~ Gos

That isn't true for the Antec Phantom 350, at least not from the data that I have seen. It went from 81% efficient at 150W and intake temperature at 31 C to 88% at 300W and intake temperature of 40 C. It did drop ever so slightly to 87% at 350W (the maximum) with the temperature at 42C.

Super Nade said it correctly, "You only need to get a unit which would suit your load." So the real question then becomes what is the load of a certain system, will the power supply be able to deliver the amount of energy needed for each voltage, and what impact does that have on the PSU's lifespan?

So if the 350W will deliver 350W but only for 6 months, it would be much better to get a 700W that would deliver 350W for 6 years. Now the Antec is warranted for three years, so Antec at least is betting that it can go three years at 350W maximum.

And of course another potential problem is the need at each voltage. The Antec 350 says 18A for line 1 and 16A for line2. But I'm also limited to the maximum draw of 334W for the +3.3V, +5V, and both the +12V together. The -12V can have 6W and the +5Vsb can have 10W (but I don't know what those two supply). Apparently one of the +12 lines supply strictly the CPU, and the other +12 line supplies everything else, but I'm not sure about that. And in reality they aren't separate lines but just one line divided into two for safety reasons according to other things I've read.

And, as a bit of a side note, it really is incredible how much energy the computer will draw if left on 24/7. Even at 250W that is 6kWh/day, 7 days a week for 42kWh, and 180kWh/month, or about 18% of your power bill. So it really does pay to get the highly efficient PSU, which will ultimately reduce your power consumption dramatically. And of course to turn off the computer when it isn't being used will save the most.

[funnyperson1]

I would have absolutely no qualms about telling you that your Phantom could power that system for years, if it weren't for those Fuhjiyyu capacitors. When subjected to heat, they die, and there should be plenty of latent heat in a passive PSU. For a 350W PSU it has excellent 12V rating, almost as much as most 500W units. I am sure that it will provide good clean power for some time, until those caps pop.

I believe that Antec has a three year warranty on all their psus, but their TruePower series are notorious for faulty capacitors. I remember one guy on newegg said he bought 26 TP450s for an internet cafe and 20 of them died within a year.

In general I don't think its a question of a 350W psu definitely not lasting as long as a 700W psu when power the same 300W+ load, it's just more likely. A good quality PSU will hold up at close to full load, look at this article:
http://legitreviews.com/article/462/1/

Everybody is like OMG you need a 2kW psu for 8800GTX sli and a quadcore, but a high quality 620W psu can run it just fine.

[mantralord]

I'm sure the 520 could've ran that fine.

[Joeteck]

We all can argue about this until hell freezes over. Each one of us already made our PS purchase we wanted. I know in my heart I made the correct choices with single 12v rail power supplies. All my rigs have Enermax in them, I love them, they've worked great for my 9 PCs. I host a website where PCP&C gave me a 750 quad for free so I can review it, and keep it. As the website is geared to push single rail power supplies. What ever you chose, I'm sure with everyone here, you'll make a great choice. Zippy is great, Seasonic, Maybe Thermal Take. Everyone has gotten burned at least once, and will never go back. But all I ask is that you do your research before you plunk down hard earned cash. Again, I would get the best you can afford so you'll never have problems again.

Good luck.

[Enablingwolf]

A good reason to overbuy on wattage.

On my current machine the 450 watt worked really good, if not great. As it evolved. I started to feel the pinch. Now I get to dump another $150 into a PSU to keep it running and stable.

I only have a 754 too. The 450 watt power suppy has hit its stable limits. Not only does the system as whole tells me, the DMM tells me. I wish now I would of had the hindsight to get a larger unit and saved the extra money. I had no clue I would have as much inside this machine as I do when I first got the PSU though.

To top it off, my overclock is hampered. Now I get he joy of taking parts out or run stock.. I won't even think of not wanting to gg higher in my overclock. Overclocking changes the whole game with power requirements.

[Burner127]

Everybody is saying get the gigantic power supply. But my calculations from http://www.extreme.outervision.com/PSUEngine say I only need 329W to power the system.

Asus says 600W "for a fully configured system." The motherboard can have at least 6 or 8 hard drives, which all take the power, while I would be using 3, along with a bunch of other things I probably won't be using, such as an optical drive. I am looking at the 65W CPU to save a bit of power there, which Asus might not have counted on.

The 350W PSU should be even more efficient since it would be running closer to capacity. I know that at startup there is an initial surge, but is that the only real reason to have the 600W supply? I thought it was possible to delay the hard drive starting for a second or two so that the surge wouldn't be as great.

And what about the Thermaltake 250W PSU in the 5.25 drive slot? Would that solve all the problems or is it not really necessary?

On the PSU calculator, what is the difference between a "Regular-Desktop" and a "High End- Desktop"?

[funnyperson1]

Basically how ridiculous your motherboard is. I think High End is like the 680i motherboards that have like 20 phase voltage regulation, 30 usb ports, 12 sata connections, and so on.

[Burner127]

Basically how ridiculous your motherboard is. I think High End is like the 680i motherboards that have like 20 phase voltage regulation, 30 usb ports, 12 sata connections, and so on.

Is mine "High End"?

[funnyperson1]

I imagine so, but I doubt it makes a huge difference to your power consumption.

[Burner127]

I imagine so, but I doubt it makes a huge difference to your power consumption.


The difference between regular desktop and high end is 13w-- for me at least.

[Joeteck]

Basically how ridiculous your motherboard is. I think High End is like the 680i motherboards that have like 20 phase voltage regulation, 30 usb ports, 12 sata connections, and so on.


And every one of them used....