What to look for in a new PSU?

[ny_driver]

Given my specs I want to make sure everything will have enough power when it's OC. There are many PSU to choose from and the prices vary greatly. I'd like to order one from new-egg tomorrow but like I said I don't know what I need. Any advice will be most appreciated:respect:

[KennyT772]

well look for a good consumer rating along with explanations of why. i am a big fan of thermal take power supplys, and just recently i purchased a hiper 580w unit. i would actually reccoment that to you also. the psu was about $85 when i ordered it. they have a bunch of other colors too.

http://www.newegg.com/Product/Product.asp?Item=N82E16817128002

[ny_driver]

That looks nice but I really want something cheaper. I am not looking for something to build off of in the future, just something to make sure the power is not an issue in my current system when it is highly overclocked.

[KennyT772]

well if you want to put your system at risk go for it. i ran my x1800/3200+ system off a thermaltake 420w psu for almost a year and she was solid. the 12v rail was stable but under load it would dip to 11.6v.

[_33]

You could always look for a good company, like OCZ, ThermalTake (Toughpower series), Antec (Truepower series), Enermax (some rare good ones), Raidmax (good prices, decent reviews), Silverstone (the top of the line IMHO).

Next, you want many 12 volt lines. Usually, they now come up with 3 or 4 lines. The good thing with multiple 12v lines is that when one peripheral uses max wattage out of one 12v line, the others don't suffer. It's much better than a single 12v line. That is the reason I switched from a class B PSU to my new TT Toughpower 600. It's rock solid power for my system. Before I used to hear my fans go slower when I launched games / 3D apps, and my voltages use to fluctuate a lot. Now with this new quality PSU, it's always stable and no fluctuation. Also note, a light weight PSU is always sign of cheapness.

You could always look for separate wires that you then plug in the PSU at your leasure, so you don't get tons of wiring in the box for nothing.

Depending on your forecasted consumption, check between 600 and 850 watts. 600 watts should be enough for most configurations, SLI / crossfire, dual core, and all those HDDs and DVD / CD drives, and the USB power. 850 watts would probably be good for dual R600 / 8800GTX card setup.

I suggest to choose wisely!

[KennyT772]

hey _33 multi-rail units are not generally better power supplys. it all depends on the design. some multi-rail designs completely separate the various rails so if one is maxed out and the other has no draw you are wasting half your power. other designs have capped draw per rail but will still share current right up to the cap.

single rail designs are still the general favorite design by overclockers as no matter what you can use every watt available. either way posting a question about a certain psu will give you a good about of feedback from that unit.

[_33]

hey _33 multi-rail units are not generally better power supplys. it all depends on the design. some multi-rail designs completely separate the various rails so if one is maxed out and the other has no draw you are wasting half your power. other designs have capped draw per rail but will still share current right up to the cap.

single rail designs are still the general favorite design by overclockers as no matter what you can use every watt available. either way posting a question about a certain psu will give you a good about of feedback from that unit.

Have you ever seen a 800 watt PSU single rail? Come on. I come back here and post after what, 2 months. Here comes those lessoning guys again.

Chow.

[ny_driver]

I found 1 of these used at a good price.....what do you think?
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=2240330&CatId=0

Should be a healthy upgrade I was thinking.:cool:

It will certainly look better than my POWMAX don't you agree?
http://home.twcny.rr.com/nydriver/pc%20with%20crappy%20looking%20cables.JPG

[pt]

Have you ever seen a 800 watt PSU single rail? Come on. I come back here and post after what, 2 months. Here comes those lessoning guys again.

Chow.

?
it has been said and proved that a single rail with a high A is better than multiple rails with lower A ;)

[ny_driver]

?
it has been said and proved that a single rail with a high A is better than multiple rails with lower A ;)so is the one I showed a single rail high A or no...please explain:confused:

EDIT:looks like it is to me

[Guttboy]

This was posted earlier with regards to PSU rankings.....maybe this will help in your decision making.....

http://www.xtremesystems.org/forums/showthread.php?t=108088

[ny_driver]

hmmm..thanks:o the one I was going to get used is on the NOT RECOMENDED list for some reason, and I don't see my current PSU (powmax) on the list. I thought that Ultra x-connect had good amperages:confused:

Oh well I will use that list and go buy a new one..hopefully pretty cheap ($50-80 )

[Guttboy]

NY....not sure how the list was come up with but it was posted here earlier. MY current PSU is tier 5 and I am pretty sure that is correct as my voltages fluctuate quite a bit.

I do know one thing...dont skimp on your PSU...I have had some computers with crappy PSU's and it is no fun not being able to do the things you want because there was a crappy PSU that you coulda spent $20 more on and had a much better one.

[overcast]

Have you ever seen a 800 watt PSU single rail? Come on. I come back here and post after what, 2 months. Here comes those lessoning guys again.

Chow.

PC Power and Cooling has single rail power supplies from 310W to 750W

If you're going to go cheap on anything, DO NOT MAKE IT BE THE POWER SUPPLY.

[ny_driver]

I decided to buy an XCLIO greatpower 600w for $99.99, this one here........:toast:

http://www.newegg.com/Product/Product.asp?Item=N82E16817189007

Not that pretty but it looked like the best tier 2 PSU at new-egg for the price. It has modular cabling and a big 140 mm fan ( I like fans) :pimp: Mostly great reviews and I have always had good luck with the egg so far. Any thoughts on my decision?

Thanks all for the sound advice:respect:

[Guttboy]

I have no experience with them but the reviews are pretty good. I guess the manual leaves something to be desired but the reviews in the "egg" are pretty comprehensive.

[_33]

?
it has been said and proved that a single rail with a high A is better than multiple rails with lower A ;)

Well, the market doesn't seem to bide by your rules. Maybe post a link to support your theory.

[pt]

Well, the market doesn't seem to bide by your rules. Maybe post a link to support your theory.

it has been posted here on tpu i don't know where
the market is most of the times wrong

[_33]

it has been posted here on tpu i don't know where
the market is most of the times wrong

I don't mind. TPU doesn't direct the market, they just spread the word. Right now the market is going towards multi 12v lines. Mine has 4, for 600w. And I have noticed much increased stability on the 12v compared to my previous PSU. Silverstone, which makes the best PSUs around do have multiple 12v lines on most of their flagship products: Element, Zeus & Strider series (http://www.silverstonetek.com/product-power.htm). Only the Olympia series has a single 12v line (wich might support part of your beliefs).

[pt]

I don't mind. TPU doesn't direct the market, they just spread the word. Right now the market is going towards multi 12v lines. Mine has 4, for 600w. And I have noticed much increased stability on the 12v compared to my previous PSU. Silverstone, which makes the best PSUs around do have multiple 12v lines on most of their flagship products: Element, Zeus & Strider series (http://www.silverstonetek.com/product-power.htm). Only the Olympia series has a single 12v line (wich might support part of your beliefs).

the market is also going towards multiple cores, and still most ppl won't use more than one ;)

[Guttboy]

This was taken from PC Power & Cooling and if you look in other spots you can find the same info by using Google......

"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."

Taken from this website.....

http://www.pcpower.com/technology/myths/

Regards!

[ny_driver]

I hope 18 amps on each rail is enough to run my cpu at 3+gHz AND my video card OC'ed plus all my fans and 4 other drives.
http://www.newegg.com/Product/Product.asp?Item=N82E16817189007

EDIT: wait is my new one considered a single rail or multi?

[_33]

This was taken from PC Power & Cooling and if you look in other spots you can find the same info by using Google......

"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."

Taken from this website.....

http://www.pcpower.com/technology/myths/

Regards!

And here is my cross argument link (http://www.jonnyguru.com/forums/showthread.php?t=691)

Everyone is going multi 12v rail, and that is a fact. Even if you see constraints in this, that is where the market is going, future proof or not. Now saying a 4x 12v rail PSU consumes more is ridiculous, as the PSU will consume as much as there are things plugged on it. Yet, it is true that you will need stronger multirail PSU than a single rail psu (my belief), sin on a multi-rail you will have some lost power potential on those multiple 12v rails. But some designs do make twin dual 12v rails, which in essence distributes each internal 12v in 2 x 12v rails that have a peak amperage each, so no big loss in amperage on that design. Yet each 12v rail should have a max amp draw of 20A as a guideline (most PSU manufacturers use 18A max, as it gives a margin for peaks up to 20A).

READ THIS QUESTION CAREFULLY:
Thought: The small ATX pins use in the 4, 6, 8, 20 and 24 pin shells are rated by Molex for 9A continous.
Now I've only seen pics of melted shells. Question to self. Will I see more in the near future with the use of high output single rail PSUs?
A decent tech setting up or maintaining equipment is one thing, a wide-eyed youngster playing with gaming hardware is another.


EDIT: Also, to add to the tought, imagine you trick the wiring from a 4 pin molex to plug your own fans, and stuff, but the wiring flashes and it shorts your 12v single rail. WHat do you think will happen to your GFX card, your CPU and all the other stuff plugged on that single rail?

[ghost101]

Dual +12V output circuits

In good old times PC power supplies used to have one power rail for each of the output voltages (+5V, +12V, +3.3V, and a couple of negative voltages), and the maximum output power on each of the rails was not higher than 150-200W. It’s only in some high-wattage server-oriented power supplies that the load on the +5V rail could be as high as 50A, i.e. 250W. This situation was changing as computers required ever more power and the distribution of power consumption among the different power rails was shifting towards +12V.

The ATX12V 1.3 standard recommends a max current of 18A for the +12V rail and this is where a problem occurred. It was about safety regulations rather than about increasing the current load further. According to the EN-60950 standard, the maximum output power on user-accessible connectors must not exceed 240VA. It is thought that higher output power may with a higher probability lead to various disasters like inflammation in case of a short circuit or hardware failure. Obviously, this output power is achieved on the +12V rail at a current of 20A while the PSU connectors are surely user-accessible.

So, when it became necessary to push the allowable current bar higher on the +12V rail, Intel Corporation, the developer of the ATX12V standard, decided to divide that power rail into multiple ones, with a current of 18A on each, the 2A difference being left as a small reserve. Purely out of safety considerations, there was no other reason for that solution. It means that the power supply does not necessarily have to have more than one +12V power rail. It is only required that an attempt to put a load higher than 18A on any of its 12V connectors would trigger off the overcurrent protection. That’s all. This simplest way to implement this is to install a few shunts into the PSU, each of which is responsible for a group of connectors. If there’s a current of over 18A on a shunt, the protection wakes up. As a result, the output power of none of the 12V connectors can exceed 18A*12V=216VA, but the combined power on the different 12V connectors can be higher than that number.

That’s why there are virtually no power supplies existing with two, three or four +12V power rails. Why should the engineer pack additional components into the already overcrowded PSU case when he can do with just a couple of shunts and a simple chip that will be controlling the voltage in them (the resistance of a shunt being a known value, the current passing through the shunt can be known if you know the voltage).

But the marketing folk just couldn’t pass by such an opportunity and now you can read on any PSU box that dual +12V output circuits help increase power and stability, the more so if there are not two but three such lines!

You think they stopped at that? Not at all. The latest trend is power supplies that have and don’t have the splitting of the +12V rail at the same time. How? It’s simple. If the current on any of the +12V output lines exceeds the 18A threshold, the overcurrent protection becomes disabled. As a result, they can still embellish the box with the magical text, “Triple 12V Rails for Unprecedented Power and Stability”, but can also add there some nonsense that the three rails are united into one when necessary. I call this nonsense because, as I have written above, there have never been separate +12V power rails. It’s impossible to comprehend the depth of that “new technology” from a technical standpoint. In fact, they try to present the lack of one technology as another technology.

:)

[AshenSugar]

click my siggy link, and fortron or epower are the best value for power and quility
you can find :)

[Guttboy]

33 I dont know jack about what is better or not. You asked for a link to support pt's theory so I tossed one at ya!

[AshenSugar]

look at the PSU guide in my siggy and dont mind that psu caculater, its crap IMHO

[_33]

33 I dont know jack about what is better or not. You asked for a link to support pt's theory so I tossed one at ya!

I know, and you did a good job! I just follow the market and pick what I think is a good product, and I mix in the blend common and good sense. I read a lot of reviews and technical briefs. I look for best product for cheapest price. Thus my system config reflects that and my poor budget.

[_33]

look at the PSU guide in my siggy and dont mind that psu caculater, its crap IMHO

The type of intro I can read in your PSU guide reflects the 2003/2004 times. But doesn't seem to reflect today's reality. More and more memory / Cooling and various other computer parts manufacturers are turning to making quality PSUs (Mushkin, Zalman, Corsair, Supermicro, Scythe, Cooler Master, ...), and Antec + Enermax and the likes, which used to be top of the line are now mostly making Class B quality PSU's compared to the newer Silverstone, OCZ, ThermalTake, and the likes.

The trends are changing (http://www.xtremesystems.org/forums/showthread.php?t=108088)because some computer parts manufacturers are tired of the less than adequate standards of the old geezers of PSU manufacturers.

Tier 2 Brands - Top Quality components With Top Notch Stability - For Those With Price/Availability Issues With Tier 1
Antec Neo HE
Akasa PowerGreen 80+
CoolMax CTG-750W/850W/1KW
Cooltek CT
Corsair HX
Enermax Liberty
Enhance ENP-GH
Fortron (FSP) GLN
iStarUSA PD2
iStarUSA PD3
OCZ GameXStream
OCZ EvoStream
PCP&C Silencer <610
Seasonic S12
Seasonic M12
Seasonic Energy Plus
SevenTeam ST <600
Silverstone EF
Supermicro/AbleCom
Thermaltake Toughpower >600W
Xclio GreatPower
Zalman ZM