The Power Supply Thread

[jonnyGURU]

Originally posted by: metalstorm203
If a video card has an auxillary power connect, does it take 100% of its juice from it when it's hooked up?

Not necessarily.

 

[ThunderLew]

I currently have this MOBO http://www.newegg.com/product/product.asp?item=N82E16813131517

I want to get a new powersupply. I was looking at this one:

http://www.newegg.com/Product/Product.asp?Item=N82E16817703001

but I am not sure if the power connectors will work since my MOBO says it has 24 power pin but the power supply list it has a main connector of 20 pin. But in the Connectors section it says it has a 24 pin.

I am confused.

 

[jonnyGURU]

Originally posted by: ThunderLew
I currently have this MOBO http://www.newegg.com/product/product.asp?item=N82E16813131517

I want to get a new powersupply. I was looking at this one:

http://www.newegg.com/Product/Product.asp?Item=N82E16817703001

but I am not sure if the power connectors will work since my MOBO says it has 24 power pin but the power supply list it has a main connector of 20 pin. But in the Connectors section it says it has a 24 pin.

I am confused.

Obviously a typo. Look at this picture: http://images10.newegg.com/NeweggImage/productimage/17-703-001-06.JPG

That's a 24-pin PSU to 20-pin mobo adapter. Obviously the PSU has a 24-pin. Never mind the fact that it's the "SLI" model which would pretty much have to be 24-pin.

 

[Howard]

some info in my sig though not as detailed as your guide.

 

[Jagbot]

To Boyo
You can see the links heres, maybe it could anser some of your question.

http://www.extremetech.com/article2/0,1697,1932958,00.asp

"Sorry for my english, i speak frech"

 

[Jagbot]

To jonnyGURU

I'm building myself a new computer system, but reading your post as me thinking about that PSU i choose for my new system.
I choosen the Silverstone ST65ZF but the article at Extremetech.com as me pusle.
In any case is a liste of my future system :

Asus A8N-SLI Premium
AMD ATHLON 64 X2 4800+
Corsair TWINX2048-3500LLPRO
Asus EN7800GTX/2DHTV (256MB)
Western Digital WD1500ADFD Raptor III (1x)
Western Digital WD3200SD Caviar RE (2x)
Lian Li PC-V2000 + (Silver)
Sunbeam Tuniq Tower 120
Windows XP Pro 64 Bits

For the PSU Silverstone ST65ZF or PC Power & Cooling TurboCool 850SSI
As for the liste it's up to prize , cause in Quebec there is 15% of taxe.

Thanks in advance,
Jagbot

 

[Howard]

Originally posted by: Jagbot
To jonnyGURU

I'm building myself a new computer system, but reading your post as me thinking about that PSU i choose for my new system.
I choosen the Silverstone ST65ZF but the article at Extremetech.com as me pusle.
In any case is a liste of my future system :

Asus A8N-SLI Premium
AMD ATHLON 64 X2 4800+
Corsair TWINX2048-3500LLPRO
Asus EN7800GTX/2DHTV (256MB)
Western Digital WD1500ADFD Raptor III (1x)
Western Digital WD3200SD Caviar RE (2x)
Lian Li PC-V2000 + (Silver)
Sunbeam Tuniq Tower 120
Windows XP Pro 64 Bits

For the PSU Silverstone ST65ZF or PC Power & Cooling TurboCool 850SSI
As for the liste it's up to prize , cause in Quebec there is 15% of taxe.

Thanks in advance,
Jagbot

The Seasonic S12-500 can supply enough power for that system and is quieter than the ST65ZF and the TC 850SSI. It is also less expensive. You can also consider the S12-600 if you are planning to use the same PSU for a system after that one.

 

[Jagbot]

Thanks for the advise, but a thing i forgeted to say is that i'm planing for this system to become sort of media serveur and a media (video) creating system. The 3 HDD in there will be felowed by another 3 or 4 HDD in the next future. Thats is why i choosen the PC-V2000 cus it can hold 12 HDD.

And now that i'm reading some post about Opteron Vs X2, i'm pulse about my processor choice ???

 

[Howard]

Originally posted by: Jagbot
Thanks for the advise, but a thing i forgeted to say is that i'm planing for this system to become sort of media serveur and a media (video) creating system. The 3 HDD in there will be felowed by another 3 or 4 HDD in the next future. Thats is why i choosen the PC-V2000 cus it can hold 12 HDD.

And now that i'm reading some post about Opteron Vs X2, i'm pulse about my processor choice ???

The S12-600 will easily handle 3-4 more HDDs. If you don't plan to overclock, the X2 is fine. Opterons tend to overclock higher.

 

[JEDIYoda]

so now this thread is getting way off topic....

I thought Johnny expressed a desire to not get into specific brands of PSU`s on this thread?

Becuase there are so many people who use a variety of different PSU`s...

There are many PSu`s on the market that would suit Jagbots needs...

Lets help Johnny keep this thread on topic and not turn it into a what brand of PSU should I get thread.....

 

[Howard]

Originally posted by: JEDIYoda
so now this thread is getting way off topic....

I thought Johnny expressed a desire to not get into specific brands of PSU`s on this thread?

Becuase there are so many people who use a variety of different PSU`s...

There are many PSu`s on the market that would suit Jagbots needs...

Lets help Johnny keep this thread on topic and not turn it into a what brand of PSU should I get thread.....

Might as well have told Jagbot to get out of the thread.

 

[starwars7]

Originally posted by: jonnyGURU
Picking the right power supply

Despite being more efficient for your electric company, power factor may be less efficient to your power supply! The components used to correct power factor generate heat. Naturally, this heat didn?t come from nowhere. It?s using, and wasting, electricity. Furthermore, the heat being introduced to the other components of the power supply causing them to run hotter and therefore less efficient.

This does sound pretty ugly, can we talk more about this? How much heat are we talking about? Does anyone else have some links on PFC that talk about its pros and cons?

Thanks

 

[SuperSix]

Originally posted by: Howard

Originally posted by: JEDIYoda
so now this thread is getting way off topic....

I thought Johnny expressed a desire to not get into specific brands of PSU`s on this thread?

Becuase there are so many people who use a variety of different PSU`s...

There are many PSu`s on the market that would suit Jagbots needs...

Lets help Johnny keep this thread on topic and not turn it into a what brand of PSU should I get thread.....

Might as well have told Jagbot to get out of the thread.

Ok - Jagbot - Please start a new thread in General Hardware to discuss your PSU choices.

That being said - I believe this thread is to discuss power supply theory and function, not to discuss "What's better for my rig" etc..

Thanks!

 

[jonnyGURU]

Originally posted by: Howard

Originally posted by: JEDIYoda
so now this thread is getting way off topic....

I thought Johnny expressed a desire to not get into specific brands of PSU`s on this thread?

Becuase there are so many people who use a variety of different PSU`s...

There are many PSu`s on the market that would suit Jagbots needs...

Lets help Johnny keep this thread on topic and not turn it into a what brand of PSU should I get thread.....

Might as well have told Jagbot to get out of the thread.

Or you.

Like SuperSix said, this isn't a "help me pick my PSU" thread. Jagbot said nothing about the Seasonic, yet you have to throw it out there because that's your preference. If he had asked if it was an adequate PSU in the first place, that would've been one thing, but he asked about the ST65ZF and you come out of left field with a Seasonic. This is exactly how every PSU thread ends up becoming a brand war. You have nothing to back your suggestion except for it's quieter and cheaper... neither of which address Jagbot's original concern. I don't want this thread to go in that direction and if it happens again I hope the mods lock the thread (again).

Of course, I'd rather that not happen because good questions are coming up. It's a good thread to leave open to address those questions. That and I'm an attention whore.

Now.. Jagbot, the ExtremeTech article shouldn't have you too worried. Remember: They switched out the PSU in a frenzy of shotgun troubleshooting to solve a problem before they even realized what the problem was! Yes, there would be a problem with running two PCI-e cards off of one rail, but if you take one of the PCI-e cards and move it to 12V4 using a Molex to PCI-e adapter. The 12V4 actually has 16A on it (label says 8A, I know) and that's plenty to go around for all of your drives AND a single PCI-e card.

The Seasonic SS-600HT would actually NOT be a better choice, because that PSU only has two 12V rails and the PCI-e's are both on the same rail and there's no way to move on of them off onto 12V2.

So in a nutshell, if you were to have a problem with an ST65ZF, prior to trying any creative connector manipulation, you'd actually have the exact same problem with the Seasonic only there's nothing you can do about it.

Thank you.

 

[jonnyGURU]

Originally posted by: starwars7

Originally posted by: jonnyGURU
Picking the right power supply

Despite being more efficient for your electric company, power factor may be less efficient to your power supply! The components used to correct power factor generate heat. Naturally, this heat didn?t come from nowhere. It?s using, and wasting, electricity. Furthermore, the heat being introduced to the other components of the power supply causing them to run hotter and therefore less efficient.

This does sound pretty ugly, can we talk more about this? How much heat are we talking about? Does anyone else have some links on PFC that talk about its pros and cons?

Thanks

Ugly, eh?

Waste in the form of heat is a given with any electronic. And with any electronic, that waste is going to vary from brand to brand depending on what components they use to build the APFC module.

Take a look at the last paragraph in that post, though. Some power supplies are 230V only APFC for EU markets and expel no more heat than a 115V model running w/o PFC. So you know the waste is minimal, it just needs to be known that it's there.

The reason I felt the need to post that is because some people think that active PFC is the end all pre-requisite to a quality PSU despite the fact that PFC isn't required in the US (and other countries) and the US customers are not being charged for poor power factor on their mains. I do believe it's safe to say that cheap power supplies NEVER come with APFC, but some good ones don't come with it either! So to overlook a decent power supply because it doesn't have a feature you do not need is silly, in my opinion.

 

[metalstorm203]

Originally posted by: jonnyGURU

Originally posted by: metalstorm203
If a video card has an auxillary power connect, does it take 100% of its juice from it when it's hooked up?

Not necessarily.

I?m only asking because let?s say you have a 4800+ cpu, 7800GTX and whatever motherboard. And on a PS that has dual 18A rails. The cpu would draw 90w, the video 110w and let?s just throw in 30w for the mobo. That?s a total of already 19A on 12v1. So when you hook up the 12v2 onto the auxillary power of the video card. How much of the amperage is lifted for v1 rail? What about when I switch to SLI with this setup.

 

[jonnyGURU]

Originally posted by: metalstorm203

Originally posted by: jonnyGURU

Originally posted by: metalstorm203
If a video card has an auxillary power connect, does it take 100% of its juice from it when it's hooked up?

Not necessarily.

I?m only asking because let?s say you have a 4800+ cpu, 7800GTX and whatever motherboard. And on a PS that has dual 18A rails. The cpu would draw 90w,

7.5A on 12V2.

the video 110w

9.2A, but on which rail depends on the power supply.

and let?s just throw in 30w for the mobo.

2.5A on 12V1.

That?s a total of already 19A on 12v1.

No it's not. You have your rails confused. As per ATX12V spec, and stated above, the CPU is on 12V2. That is your 2x2 power connector. The spec states that the ATX connector and hard drive/floppy drive Molexes are on 12V1. The rail OTHER THAN the CPU's. The spec does not specify SATA and PCI-e, so many power supply manufacturers take liberty with how these connectors are split up.

In hind sight, I wish I had specified how the rails are split up for all of the power supplies I've reviewed. But I never thought about it before everyone started having problems with their high end video cards.

So when you hook up the 12v2 onto the auxillary power of the video card. How much of the amperage is lifted for v1 rail? What about when I switch to SLI with this setup.

Ok.. So lets fix your numbers.

Typical ATX12V config, you only have 7.5A on 12V2. Unfortunately, that means everything else is on 12V1. So your 11.7A would be on 12V1 and you haven't taken into account hard drives, fans, lights, etc.

THAT'S why there's been problems. That's why single rails solve the problem. But also in the case of the Silverstone quad-rails or any power supply that puts the PCI-e connectors on the 12V2 with the CPU, like the X-Finity I use, or even a tri-rail PSU like the Antec NeoHE which gives you two modular connectors dedicated to the 12V3 rail, all you have to do is move one of the PCI-e connectors off of the same rail as the other PCI-e connector. Quick fix.

I imagine you could certainly move a PCI-e off of 12V1 onto 12V2 if you have a PSU with both PCI-e connectors on 12V1, but there certainly isn't any kind of adapter to do that. You'd have to take apart the PSU and solder the cable down to the same spot you see the 4-pin 2x2 P4 connector soldered down.

 

[metalstorm203]

Yes. I got the rails confused. My PS has a seperate cable with two 6-pin video card pci-express adapters on it and nothing else - so I assume this is the v1 rail.

 

[jonnyGURU]

The S-12-600 in your sig? Yeah. I believe that's on 12V1 and they only have the CPU on 12V2.

And it doesn't matter if there are other things on the same cable. Typically, there aren't other connectors on a PCI-e cable. What matters is where it's soldered down inside the power supply.

 

[Jagbot]

Thanks jonnyGURU for your response, i'm sorry for transforming this thread into "help me choose my PSU". In fact i have several shose for my new PSU, 6 in fact and the Seasonic was'nt in them because of the two 12V rails, that is because of your information earlyer about PSU and 12V rails.
For the question about a second video card, the anser is there will be a second video card, not in the nere futur but maybe in a year and a half or so, because i will have, and maybe need, multi-monitor setup, but not a SLI setup.

I have a question about how to calculate the real heat generated by PSU.
Exemple :
Enermax Liberty620W
at 120V X 9A = 1080W
at 240V X 4A = 960W

Ok i know that higher the tension better the effeciency is, but that calcul tell me that for a 620W in the outlet there is (min of) 960W in the inlet for a efficiency of about 80% or so.
Now the number tell me there is about ~ 340W of heat produce by the PSU and (620W/960)X 100 = 64.58 % efficiency.
If i'm wrong in my calcul tell me so

Thanks
(P.S. the Enermax Liberty620W is just a exemple OK)

 

[metalstorm203]

Originally posted by: jonnyGURU
The S-12-600 in your sig? Yeah. I believe that's on 12V1 and they only have the CPU on 12V2.

And it doesn't matter if there are other things on the same cable. Typically, there aren't other connectors on a PCI-e cable. What matters is where it's soldered down inside the power supply.

Yes. It's the PS in my sig. Thanks for taking time to explain things about power supplies. It really hasn't been an issue for me until just recently so it's been a learning experience.

 

[jonnyGURU]

Originally posted by: Jagbot

I have a question about how to calculate the real heat generated by PSU.
Exemple :
Enermax Liberty620W
at 120V X 9A = 1080W
at 240V X 4A = 960W

Ok i know that higher the tension better the effeciency is, but that calcul tell me that for a 620W in the outlet there is (min of) 960W in the inlet for a efficiency of about 80% or so.
Now the number tell me there is about ~ 340W of heat produce by the PSU and (620W/960)X 100 = 64.58 % efficiency.
If i'm wrong in my calcul tell me so

At 620W, the heat given off before the AC is even converted to DC may in fact be 120W more on a 120VAC outlet vs. a 240VAC outlet. But I couldn't say for sure w/o putting a 620W load on the PSU and testing it with both a 120V and 230V AC input. Your numbers are based on a max load, where there's max resistance causing the maximum loss. Nobody uses a 620W power supply to put out 620W and hardly anybody measures there power supplies at max load... at least under 120V conditions.

At lower wattages, the resistance may be lower. In fact, so low that the only heat lost on the AC side would be at the active PFC. So you may be looking at something more along the lines of 3A @ 120V and 1.5A @ 240W.

 

[GalvanizedYankee]

Originally posted by: jonnyGURU

Originally posted by: starwars7

Originally posted by: jonnyGURU
Picking the right power supply

Despite being more efficient for your electric company, power factor may be less efficient to your power supply! The components used to correct power factor generate heat. Naturally, this heat didn?t come from nowhere. It?s using, and wasting, electricity. Furthermore, the heat being introduced to the other components of the power supply causing them to run hotter and therefore less efficient.

This does sound pretty ugly, can we talk more about this? How much heat are we talking about? Does anyone else have some links on PFC that talk about its pros and cons?

Thanks

Ugly, eh?

Waste in the form of heat is a given with any electronic. And with any electronic, that waste is going to vary from brand to brand depending on what components they use to build the APFC module.

Take a look at the last paragraph in that post, though. Some power supplies are 230V only APFC for EU markets and expel no more heat than a 115V model running w/o PFC. So you know the waste is minimal, it just needs to be known that it's there.

The reason I felt the need to post that is because some people think that active PFC is the end all pre-requisite to a quality PSU despite the fact that PFC isn't required in the US (and other countries) and the US customers are not being charged for poor power factor on their mains. I do believe it's safe to say that cheap power supplies NEVER come with APFC, but some good ones don't come with it either! So to overlook a decent power supply because it doesn't have a feature you do not need is silly, in my opinion.

When studying(chosen word)/shopping PSUs it does seem the better units do have APFC.
I say this as an observation not a contest of knowledge. Even the highly efficiant PSUs
listed at http://www.80plus.org/ have APFC. This spec is more enviromentally friendly and
if it does help the power providers as Dan's DATA states, my personal feeling is so what.
There is a reason the tree huggers of the EU requior this in their spec

I highly reccomend to all that have an interest in putting a finer point on their knowledge
about APFC, give this a slow read. The whole artcle is worth the time spent on it, imho.
http://www.xbitlabs.com/articles/other/display/psu-methodology_8.html

Note the comment made about UPS selection when APFC is in place. A small detail for sure
but God and the devil are in the details.

Just so you don't think I'm green through&through all 4 PSUs here hover around 70%
efficiant and have APFC.

...Galvanized


EDIT: The question is. Why do most all of the higher end PSUs have APFC.?

Since the American market is so large and APFC is so non-essential why offer it here
in the first place.?

The Dan's DATA link has been posted on this forum many times and no one disputes
it ever.
I look forward to a direct answer or links other than Xbit Labs.
___________________________________________________________________________

EDIT#2

Only because it is so easy to search, I went to Newegg and looked at PSUs w/o PFC,
price range from $65 to $165 and found few that I would seriously consider buying.

I searched again, $65 to $165 w/Active PFC and found many worthy of my consideration
and monie$.

My question that you chose to avoid was not about a particular PSU but about the quality
of PSU construction. It seems that those w/APFC are more highly rated.

Last post in this thread.


...Galvanized

 

[computer]

Can anyone tell me if such a thing exists?

A PS with adjustable rails, AND a "modular" cable design like these?
http://www.ocztechnology.com/images/products/accessories/b/ModStreamfull.jpg
Even OCZ doesn't. That one at the link doesn't have adjustable voltage, and theirs that DO have adjustable voltage doesn't have the separate cables! Tagan makes a really nice 530 and 580 watt unit with the separate cables, but no adjustable voltage.

Thanks.

 

[JEDIYoda]

you really should be making a new thread....

This is NOT about particular brands per say...lets keep this thread clean!!