jonnyGURU Forums
Home Site Search Reviews Articles Contest Links PSU FAQs  


Go Back   jonnyGURU Forums > Computer Hardware > PC Power Supply Discussion

PC Power Supply Discussion Troubleshooting and discussion of computer power supplies

Reply
 
Thread Tools Display Modes
  #1  
Old 01-23-2008
nullack nullack is offline
micro ATX User
 
Join Date: Oct 2007
Posts: 14
Thanks: 0
Thanked 0 Times in 0 Posts
Default Need >1000W Single Rail Tri Sli ESA PSU

What psu unit can I buy with the following:

Must have support for tri sli - i.e. 3 6pin and 3 8pin pcie connectors

Must have single rail

Must be over 1000watts output

ESA support would be a nice bonus

The Thermaltake toughpower isnt single rail. I just dont like having to balance the rails.
Reply With Quote
  #2  
Old 01-23-2008
Spectre Spectre is offline
Pinball Wizard
 
Join Date: Oct 2006
Location: Moderator
Posts: 4,100
Thanks: 15
Thanked 98 Times in 62 Posts
Default

Quote:
Originally Posted by nullack View Post
I just dont like having to balance the rails.
Why do you think this is a problem?
Reply With Quote
  #3  
Old 01-23-2008
jonnyGURU's Avatar
jonnyGURU jonnyGURU is offline
Site Founder
 
Join Date: Oct 2006
Location: jonnyGURU forums, of course!
Posts: 15,096
Thanks: 483
Thanked 1,926 Times in 1,189 Posts
Default

I'm stuck on this... "must have single rail"????

Who's Kool-Aid have you been drinking????
__________________
Rest in peace Mike Clements, aka "Yellowbeard"

Rest in peace Joerg Theissen, aka "GI Joe"
Reply With Quote
  #4  
Old 01-23-2008
nullack nullack is offline
micro ATX User
 
Join Date: Oct 2007
Posts: 14
Thanks: 0
Thanked 0 Times in 0 Posts
Default

PcPower say:

"ARE MULTIPLE 12-VOLT RAILS BETTER THAN A SINGLE 12-VOLT RAIL?
With all the hype about multiple 12-volt rails (ads claim that two rails is better than one, five is better than four, etc.), you'd think it was a better design. Unfortunately, it's not!

Here are the facts: A large, single 12-volt rail (without a 240VA limit) can transfer 100% of the 12-volt output from the PSU to the computer, while a multi-rail 12-volt design has distribution losses of up to 30% of the power supply's rating. Those losses occur because power literally gets “trapped" on under-utilized rails. For example, if the 12-volt rail that powers the CPU is rated for 17 amps and the CPU only uses 7A, the remaining 10A is unusable, since it is isolated from the rest of the system.

Since the maximum current from any one 12-volt rail of a multiple-rail PSU is limited to 20 amps (240VA / 12 volts = 20 amps), PCs with high-performance components that draw over 20 amps from the same rail are subject to over-current shutdowns. With power requirements for multiple processors and graphics cards continuing to grow, the multiple-rail design, with its 240VA limit per rail, is basically obsolete.

PC Power and Cooling is once again leading the industry. All of our power supplies now feature a large, single 12-volt rail. The design is favored by major processor and graphics companies, complies with EPS12V specs (the 240VA limit is not a requirement) and is approved by all major safety agencies such as UL and TUV.3 "

I have observed on various overclocking forums that people have reported gaining higher clocks on the extreme ends of overclocking my moving from multi rail to single rail. Especially on quad core cpus.

I do appreciate this is anecdotal at best, and I am honestly interested in getting to the science of the matter in determining what the best PSU is for me. If there is a solid, scientific reason why single rail PSUs are not in anyway better than multi rails, then Im happy to take it off the list But I would like to learn more as to why.

I also think the 1500watt thermaltake toughpower doesnt support ESA.
Reply With Quote
  #5  
Old 01-24-2008
Stefan555's Avatar
Stefan555 Stefan555 is offline
Shuttle user
 
Join Date: Nov 2007
Location: Sweden
Posts: 160
Thanks: 0
Thanked 1 Time in 1 Post
Default

A multiple rail PSU has its big advantages over single rail PSU’s.

-A multiple rail PSU generates less heat, because less current is put through each rail. A PSU generating more heat requires a more advanced cooling solution and other components in the PSU must be dimensioned survive the higher currents. A multiple rail PSU means cheaper PSU due to the cheaper components.

-A multiple rail unit is more silent due to the smaller dimensions of components and cooling solution

-If one rail goes short, the other rails are not affected on a multiple rail PSU. If a single rail goes short, well…there is not much left.

High currents on each rail increase the risk of instability.

-It is not really correct a PSU with single rail can transfer 100% of the +12V output to the PSU. It is true for the lower wattage PSU’s, but for the high wattage PSU’s it is quite often a multiple rail PSU can put more +12V output to the computer than a single rail PSU.

Singe rail units
-Silverstone Olympia 1000W can put through 96% of the output through the +12V (960W)
-Silverstone Decathlon 1200W can put through 90% of the output through the +12V (1080W)
-PCP&C Turbo-Cool 1000W can put through 86% of the output through the +12V (860W)
-PCP&C Turbo-Cool 1200W can put through 90% of the output through the +12V (1080W)

Multiple rail units
-Silverstone ZM1000M can put through 95% of the output through the +12V (1140W)
-Silverstone ST-1000NV can put through 84% of the output through the +12V (840W)
-TT Toughpower 1200W can put through 99% of the output through the +12V (1188W)
-TT Toughpower 1000W can put through 98% of the output through the +12V (984W)

You say there is a limit of 20A on each rail on a multiple rail unit. It’s not correct, you can find many multiple rail units with a limit of more than 20A on one or several rails. In addition, it’s just the specification, the reality is often something else.

The advantage of a single rail unit is; nobody has to consider the distribution on the rails, not the designer, not the manufacturer, not the customer.

But it is true; every Amp not used on each rail on a multiple rail PSU is a lost Amp, but with a proper rail distribution that suits the rigg, the losses can be minimized. An example, it doesn’t make any sence to buy an Enermax Galaxy 850W to a single cpu rigg, The Galaxy is for dual cpu’s where 408W on two +12V rails are for the cpu’s only. The rest of the components are sharing 408 Watts on three +12V rails.

Last edited by Stefan555; 01-24-2008 at 04:22 AM.
Reply With Quote
  #6  
Old 01-24-2008
sdbardwick's Avatar
sdbardwick sdbardwick is offline
1kW User
 
Join Date: Jul 2007
Posts: 117
Thanks: 0
Thanked 7 Times in 2 Posts
Default

Quote:
Originally Posted by Stefan555 View Post
A multiple rail PSU has its big advantages over single rail PSU’s.

-A multiple rail PSU generates less heat, because less current is put through each rail. A PSU generating more heat requires a more advanced cooling solution and other components in the PSU must be dimensioned survive the higher currents. A multiple rail PSU means cheaper PSU due to the cheaper components.

-A multiple rail unit is more silent due to the smaller dimensions of components and cooling solution

-If one rail goes short, the other rails are not affected on a multiple rail PSU. If a single rail goes short, well…there is not much left.

High currents on each rail increase the risk of instability.

-It is not really correct a PSU with single rail can transfer 100% of the +12V output to the PSU. It is true for the lower wattage PSU’s, but for the high wattage PSU’s it is quite often a multiple rail PSU can put more +12V output to the computer than a single rail PSU.

Singe rail units
-Silverstone Olympia 1000W can put through 96% of the output through the +12V (960W)
-Silverstone Decathlon 1200W can put through 90% of the output through the +12V (1080W)
-PCP&C Turbo-Cool 1000W can put through 86% of the output through the +12V (860W)
-PCP&C Turbo-Cool 1200W can put through 90% of the output through the +12V (1080W)

Multiple rail units
-Silverstone ZM1000M can put through 95% of the output through the +12V (1140W)
-Silverstone ST-1000NV can put through 84% of the output through the +12V (840W)
-TT Toughpower 1200W can put through 99% of the output through the +12V (1188W)
-TT Toughpower 1000W can put through 98% of the output through the +12V (984W)

You say there is a limit of 20A on each rail on a multiple rail unit. It’s not correct, you can find many multiple rail units with a limit of more than 20A on one or several rails. In addition, it’s just the specification, the reality is often something else.

The advantage of a single rail unit is; nobody has to consider the distribution on the rails, not the designer, not the manufacturer, not the customer.

But it is true; every Amp not used on each rail on a multiple rail PSU is a lost Amp, but with a proper rail distribution that suits the rigg, the losses can be minimized. An example, it doesn’t make any sence to buy an Enermax Galaxy 850W to a single cpu rigg, The Galaxy is for dual cpu’s where 408W on two +12V rails are for the cpu’s only. The rest of the components are sharing 408 Watts on three +12V rails.
My BS detector just went off the scale.
Reply With Quote
  #7  
Old 01-24-2008
MrWicked1968's Avatar
MrWicked1968 MrWicked1968 is offline
Flux Capacitor User
 
Join Date: Oct 2006
Location: East Tennessee
Posts: 1,590
Thanks: 3
Thanked 0 Times in 0 Posts
Default

wow, he quoted PC P&C FUD. where's jediyoda?


edit: woot! my 500th post!
__________________
Rig 1: Phenom II X2 550-Asus M5A78L-MLX--2x4 Patriot DDR3 1333--Asus Formula HD4770--Enermax Triathlor 450--LG Flatron W2252TQ--Win 10 x64
Rig 2: Core i3 6300--Asrock Z170M Extreme4--2x8 Adata DDR4 2400--EVGA GTX 750Ti--Corsair CX500M--Corsair Hydro H55--Windows 7 x64
Reply With Quote
  #8  
Old 01-24-2008
ianm2 ianm2 is offline
Flux Capacitor User
 
Join Date: Dec 2006
Location: UK
Posts: 514
Thanks: 0
Thanked 0 Times in 0 Posts
Default

people have been brainwashed with pc/p/c just like another area I know of.

there is a hifi company in the uk called naim, they inspire such utter blinkered following, such that people would say how high if they said jump.

why should a multi 12 volt rail be limited to 240VA?

surely its dependant on the rating of the devices that 'power' that rail?

rahter like a single rail, a multi rail can be effectively a collection of single rails?

and 17A rating doesn't mean 10 amps are wasted.

if its 17A and its drawing 7A, then so much the better

1/ the devices are underrated, so longer life
2/ it leaves more 'headroom' for other areas to draw more current.

someone doesn't understand entirely what they are talking about.

not that I do on some things.

in fact, that pcp/c propaganda, unless I am missing the point, is such utter bollux I will never buy one of their products.

either someone tell me I am wrong, or they are.

power doesn't get 'trapped' there is no 30% loss in a multi rail. loss is different to under use.

I think we need a guru, not necc. jonny, to disseminate their claims once and for all, I dont' have the full grasp, but my BS meter too has gone off the scale.

nullack, I will apologise if I am wrong, but you have been taken in, there's one born every minute, unless you have a vested interest in pushing pcp/c?

my my, they do push it hard, why don't they add " we make them in china, so we can screw more money out of the suckers here, made for nothing in china, sold for a bomb in the USA"
Reply With Quote
  #9  
Old 01-24-2008
jonnyGURU's Avatar
jonnyGURU jonnyGURU is offline
Site Founder
 
Join Date: Oct 2006
Location: jonnyGURU forums, of course!
Posts: 15,096
Thanks: 483
Thanked 1,926 Times in 1,189 Posts
Default

Quote:
Originally Posted by nullack View Post
PcPower say:

"ARE MULTIPLE 12-VOLT RAILS BETTER THAN A SINGLE 12-VOLT RAIL?"....*snip*
Ok.... You realize that what's on PC Power's website is not an over all PSU FAQ, but is actually marketing, right?

Or at least you know that now based on what everyone here is telling you.

Fear not the multiple +12V rail PSU. If you have a larger unit, with more +12V rails at a greater amperage per rail (20A+) then you're good.

PCP&C got caught with their pants down my not properly distributing power across their multiple +12V rails back when they were doing their 850W and 1000W PSU's with four +12V rails. Instead of correcting the problem, they did away with the splitting of the +12V rails altogether and then created marketing fluff to make you question why +12V rails are split in the first place.
__________________
Rest in peace Mike Clements, aka "Yellowbeard"

Rest in peace Joerg Theissen, aka "GI Joe"
Reply With Quote
  #10  
Old 01-24-2008
jonnyGURU's Avatar
jonnyGURU jonnyGURU is offline
Site Founder
 
Join Date: Oct 2006
Location: jonnyGURU forums, of course!
Posts: 15,096
Thanks: 483
Thanked 1,926 Times in 1,189 Posts
Default

DuckieHo and I had a captive audience at Overclock.net and I think these are good discussions to follow if questioning the validity of split +12V rails, how the rails are split, why they split them, etc.

http://www.overclock.net/power-suppl...ification.html

and

http://www.overclock.net/power-suppl...ails-work.html

Yes, they're both the same OP. He was really confused.
__________________
Rest in peace Mike Clements, aka "Yellowbeard"

Rest in peace Joerg Theissen, aka "GI Joe"
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Single vs. Multiple +12V rails: The splitting of the +12V rail jonnyGURU PC Power Supply Discussion 184 08-01-2013 03:38 PM
Will my aging single rail 14a +12 Zalman run new rig? SixIron PC Power Supply Discussion 10 01-01-2011 12:33 AM
Single or Multi 12v rail? kimandsally PC Power Supply Discussion 13 02-16-2009 08:36 AM
Single rail opposed to.. OnDborder PC Power Supply Discussion 2 01-02-2007 11:24 AM
Introducing: The single 12V rail 1kW! jonnyGURU PC Power Supply Discussion 19 10-21-2006 11:28 AM


All times are GMT -4. The time now is 03:43 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Copyright © JonnyGURU.com 2000 -