Whats the point of a 1250w.. and FSP has been going downhill from what I have heard...

ShadowFoldWhats the point of a 1250w.. and FSP has been going downhill from what I have heard...

As of now nothing I know of, e-pen maybe. Until we can run 4 4870 X2s :).

Shouldn't that be 1100w, not 1010w?

FSP power supplies have always treated me well. These look like nice power supplies, I wish I had a use for all that power though, and I'm sure they will be insanely priced.

90% effieciency? if they downgrade their wattage usage, I will finally have no shame getting my hands on a PSU that's 600W-750W. Who gives a crap anyway if FSP is going downhill, after all there are other companies we want to go downhill, such as Coolmax.

fsp is actually a preety decent brand.. and 90 percent efficency is insane, but its too expected now a days with killowatt psu's, especcially since their main use is for servers and all.

Not bad though the colors are Ugly. FSP hasnt been going down, they just havent been doing much. I wish they had some sort of Rail Combine. 20A on 6 rails doesnt leave me all "warm and toasty".

WarEagleAUNot bad though the colors are Ugly. FSP hasnt been going down, they just havent been doing much. I wish they had some sort of Rail Combine. 20A on 6 rails doesnt leave me all "warm and toasty".

It is better than 120A on one rail.

No its not, 20A on each of the 6 rails doesn't necessary mean its better than one single 120A rail, the multi 12v rail = better is a myth.

insiderNo its not, 20A on each of the 6 rails doesn't necessary mean its better than one single 120A rail, the multi 12v rail = better is a myth.

Not really, just the reasoning behind multiple 12v rails = better is usually a myth. Multiplie 12v rails in high output PSU's is better. Any more than 40A and the rails should be split. The only argument that ever makes sense for the single rail side, is that you get the full use of the all amps, which just isn't true anyway.

newtekie1Not really, just the reasoning behind multiple 12v rails = better is usually a myth. Multiplie 12v rails in high output PSU's is better. Any more than 40A and the rails should be split.

thats correct, it allows the cost of the psu to be lower, and is safer because the rails are capped, so it causes a little less ripple and much less voltage in the case of any malfunction. plus when you have a huge server with lots of components, you're better off having seperate rails.

Do some research on the web, and you'll find out that there is almost no such beast as "multiple lines", at least not in the way manufacturers want you to tink of it. Very few power supplies have 2 transformers inside, and even then what you've got are 2 power lines... From then on it's clear that whether the power is delivered over 6 separate cables or only 2, it's completely a matter of taste - except for the fact that running i.e. 100A on a sinlge cable isn't exactly safe (and not allowed by the ATX standard, of course). I don't see any problem in having a 20A current limit on a 12V wire, anyway - I can't think of a device that would need 240W on that sinlge wire alone.

As for the "90% efficiency" claim - even if it were true, it wouldn't happen before say 500W load, and you'll have to live with mediocre efficiency at the lower digits, where even high-end PC reside when idle. Bottom line, those 1250W beasts seem pretty useless to me (and they are clearly consumer models... server PSU with LED fan, come on...). Thanks god, nVidia and ATI still haven't invented the uber-GPU that would make any sense of them.

Exactly, multi rails is just pure marketing BS, there is no such thing they all come off the same 12v line.

If I were to buy such a beefy PSU it would be something like this: www.pcpower.com/power-supply/turbo-cool-1200.html

www.pcpower.com/technology/myths/#m8

8. 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

You will find OCZ PSUs (who also own PCP&C now) are single rail.

240w limit obsolete? Give me a break, show me a component that uses 240w and doesn't pull it from multiple rails already.

Up to 30% losses? Really. Please at least use a little common sense instead of just believing anything you read. I'll explain, we'll use these power supplies as examples to get the numbers, but the idea applies to all PSU's.

At 20A per 12v rail is 240w right? Now with 6 rails that makes how many watts total? 1440w... So if we combine all those rails into one 120A rail, you get a single rail that is 1440w, the PSU is only rated for 1200w. Take into consideration the other voltages in the power supply, you are looking about 100w out of that 1200 gone to those. You then have about 1100w left to drive a 1440w rail. I'm not going to go through the math, because I am lazy, but I'm pretty sure that is almost 25% loss right there regardless of rail configuration.

So sorry to break it to you, but PCP&C is wrong. Even with a large single rail, 100% of the 12v output can't be transfered to the computer, and there isn't a component on the market today that draws 240w from a single rail. And the few graphics cards that come close to that 240w power draw, draw it from at lest two seperate rails, most actually 3.

The reason for multi rail power supplies, are pretty much what panchoman said, and the reason that if you read some real good reviews of OCZ and PCP&C power supplies, you will see a lot of complaints of voltage drops under load.

my voltages went up when I had my single-rail tagan under load :p. One just has to do a bit of pre-planning with a multi-rail setup, as opposed to the single, and realize what combined amperage/wattage is

insiderExactly, multi rails is just pure marketing BS, there is no such thing they all come off the same 12v line.

If I were to buy such a beefy PSU it would be something like this: www.pcpower.com/power-supply/turbo-cool-1200.html



You will find OCZ PSUs (who also own PCP&C now) are single rail.

That's propaganda from a psu manufacturer. It's to be taken with a grain of salt.

Neither design is better than the other. Pros and Cons exist for both.

Here's a better explanation from Jonny Guru.

www.jonnyguru.com/forums/showthread.php?t=3990

Jonny GuruWhy do some people FUD that single is better?

Because there are a few examples of companies that have produced power supplies with four +12V rails, something that in theory should provide MORE than ample power to a high end gaming rig, and screwed up. These PSU companies followed EPS12V specifications, which is for servers, not "gamers". they put ALL of the PCIe connectors on one of the +12V rails instead of a separate +12V rail. The +12V rail was easily overloaded and caused the PSU to shut down. Instead of correcting the problem, they just did away with the splitting of +12V rails altogether. Multiple +12V rail "enthusiast" PSU's today have a +12V rail just for PCIe connectors or may even split four or six PCIe connectors up across two different +12V rails. The rails themselves are capable of far more power output than any PCIe graphics card would ever need. In fact, Nvidia SLI certification these days REQUIRE that the PCIe connectors be on their own +12V rail to avoid any problems from running high end graphics cards on split +12V rail PSU's.
There's less components and less engineering to make a PSU that DOES NOT have the +12V rail split up, so it's cheaper to manufacturer (about $1.50 less on the BOM, $2 to $3 at retail) and typically this cost savings is NOT handed down to the consumer, so it actually behooves marketing to convince you that you only need single +12V rails.

But some people claim they can overclock better, etc. with a single +12V rail PSU

B.S. It's a placebo effect. The reality is that their previous PSU was defective or just wasn't as good as their current unit. If the old PSU was a cheap-o unit with four +12V rails and the new one is a PCP&C with one +12V rail, the new one isn't overclocking better because it's a single +12V rail unit. It's overclocking better because the old PSU was crap. It's only coincidental if the old PSU had multiple +12V rails and the current one has just one.

The only "problem" the occurs with multiple +12V rails is that when a +12V rail is overloaded (for example: more than 20A is being demanded from a rail set to only deliver up to 20A), the PSU shuts down. Since there are no "limits" on single +12V rail PSU's, you can not overload the rails and cause them to shut down..... unless you're using a "too-small" PSU in the first place. Single +12V rails do not have better voltage regulation, do not have better ripple filtering, etc. unless the PSU is better to begin with.

Jonny GuruThe bottom line is, for 99% of the folks out there single vs. multiple +12V rails is a NON ISSUE. It's something that has been hyped up by marketing folks on BOTH SIDES of the fence. Too often we see mis-prioritized requests for PSU advice: Asking "what single +12V rail PSU should I get" when the person isn't even running SLI! Unless you're running a plethora of Peltiers in your machine, it should be a non-issue assuming that the PSU has all of the connectors your machine requires and there are no need for "splitters" (see Example 1 in the previous bullet point).

The criteria for buying a PSU should be:

* Does the PSU provide enough power for my machine?
* Does the PSU have all of the connectors I require (6-pin for high end PCIe, two 6-pin, four 6-pin or even the newer 8-pin PCIe connector)?
* If using SLI or Crossfire, is the unit SLI or Crossfire certified (doesn't matter if a PSU is certified for one or the other as long as it has the correct connectors. If it passed certification for EITHER that means it's been real world tested with dual graphics cards in a worst case scenario).

Figure out if there are any variables that may affect the actual output capability of the PSU:

* Is the PSU rated at continuous or peak?
* What temperature is the PSU rated at? Room (25° to 30°C) or actual operating temperature (40°C to 50°C)
* If room temperature, what's the derating curve? As a PSU runs hotter, it's capability to put out power is diminished. If no de-rate can be found, assume that a PSU rated at room temperature may only be able to put out around 75% of it's rated capability once installed in a PC.

After that, narrow selection down with finer details that may be more important to others than it may be to you....

* Does the unit have power factor correction?
* Is the unit efficient?
* Is the unit quiet?
* Is the unit modular?
* Am I paying extra for bling?
* Do I want bling?

@newtekie - A TEC can draw 240W off of a single rail, and yes, some people are crazy enough to run them off of their main psu. lol

ShadowFoldWhats the point of a 1250w.. and FSP has been going downhill from what I have heard...

jbunch07As of now nothing I know of, e-pen maybe. Until we can run 4 4870 X2s :).

even 3 4870x2 need this , 4870x2 =350w full load 3 4870x2 =1050w this is only card's with other part's like many hdd in raid i think try think in 1500w cuz the efficiently of 1250w about 1100w and 1500w about 1300w

Wile EThat's propaganda from a psu manufacturer. It's to be taken with a grain of salt.

Neither design is better than the other. Pros and Cons exist for both.

Here's a better explanation from Jonny Guru.

www.jonnyguru.com/forums/showthread.php?t=3990





@newtekie - A TEC can draw 240W off of a single rail, and yes, some people are crazy enough to run them off of their main psu. lol

Reread my posts "No its not, 20A on each of the 6 rails doesn't necessary mean its better than one single 120A rail, the multi 12v rail = better is a myth"

The quote you gave basically agreed with the line PCP&C gave, nether claimed its better but rather the 20A limit per line isn't there, hardcore overclockers can easily pull more than 20A off one 12v rail.

Wile E@newtekie - A TEC can draw 240W off of a single rail, and yes, some people are crazy enough to run them off of their main psu. lol

Ah, didn't think of a TEC, though I would hope that anyone using a TEC that powerful with the knowledge required to do it without killing anything, would also have the knowledge to either run it off multiple rails or better yet off an aux power supply. But I do know that this isn't always the case.

insiderReread my posts "No its not, 20A on each of the 6 rails doesn't necessary mean its better than one single 120A rail, the multi 12v rail = better is a myth"

The quote you gave basically agreed with the line PCP&C gave, nether claimed its better but rather the 20A limit per line isn't there, hardcore overclockers can easily pull more than 20A off one 12v rail.

Yes, that was your statement, but then you preceeded to back that statement up with a statement that is implying that a single rail is better. It didn't come right out and say it, but it was implied throughout the entire article. And as Wile E said, that is just PSU Manufacturer marketting BS and there are really Pros and Cons to both.

I just don't feel comfortable with having a large single 12v rail with the PSU is rated for more then 40A, but as already said it is really just personal preference. Maybe it is my small background in electrical work which tells me an 18AWG wire isn't meant to hold up under much more than 20A at 12v.