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Will this PSU be okay?

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May 28, 2009 11:13:18 PM

I'm upgrading my system, but I was wondering whether the PSU I have at the moment will be powerful enough.

System specs:

CPU: AMD Phenom II X3 720 Black Edition
Motherboard: Asus M4A78T-E
Graphics Card: 1 GB Asus GTS 250 Dark Knight
Hard Drive 1: 250 GB Western Digital WD2500JB
Hard Drive 2: 500 GB Western Digital WD5002ABYS
DVD/RW Drive: LG OEM DVD/RW drive
Sound Card: Soundblaster Audigy 5.1

Current PSU: 400MHz

More about : psu

May 28, 2009 11:59:14 PM

I say upgrade the PSU without a doubt. Just because a PSU will power your system don't necessarily mean its okay. Being under powered can be associated with many problems including early parts failure especially HDD's. The AMD 790GX chipset supports Crossfire X at a reduced bandwidth rate so I'll give you two good options.

Without CF:
http://www.newegg.com/Product/ProductList.aspx?Submit=E...

With CF:
http://www.newegg.com/Product/ProductList.aspx?Submit=E...

Note: The 850w may be a bit overkill but I like overkill, you would probably be okay with a 750w PSU.
a b ) Power supply
May 29, 2009 2:37:17 AM

starams5 said:
I say upgrade the PSU without a doubt. Just because a PSU will power your system don't necessarily mean its okay. Being under powered can be associated with many problems including early parts failure especially HDD's.


You don't even know what PSU he has.
Related resources
a b ) Power supply
May 29, 2009 2:38:14 AM

magic_ghost said:
Current PSU: 400MHz


Try again. What make and model?
May 29, 2009 2:44:49 AM

Are you blind?
May 29, 2009 2:47:16 AM

@the animal

Let me ask it another way, would you run a 400w PSU with those specs?
May 29, 2009 3:18:36 AM

starams5 said:
@the animal

Let me ask it another way, would you run a 400w PSU with those specs?


Depending on the PSU's 12VDC rails, I would have no issues with it. TheAnimal is correct, more info required.
May 29, 2009 3:22:29 AM

I totally disagree with you and your buddy, you recommend what you want to recommend and I'll do the same.
May 29, 2009 3:48:16 AM

starams5 said:
I totally disagree with you and your buddy, you recommend what you want to recommend and I'll do the same.


The best PSU calculator out there seems to think the OP needs 250W. That is guessing a bit on some of the OP's components, but still even guessing low a 400W quality PSU should more than suffice. You seem to have a penchant for recommending 2x the power supply that a user needs, never mind that the PSU will be really ineffecient at those loads.

As theAnimal has already posted, more info required.
May 29, 2009 3:52:59 AM

starams5 said:
I totally disagree with you and your buddy, you recommend what you want to recommend and I'll do the same.

A good quality 400 watt PSU will easily drive his system and give plenty of overclocking headroom. If you have any doubts, theres dozens of threads/articles around the place.
May 29, 2009 3:56:54 AM

g3force said:
A good quality 400 watt PSU will easily drive his system and give plenty of overclocking headroom. If you have any doubts, theres dozens of threads/articles around the place.


You put it in quotes but I don't think you read what I said. "you recommend what you want to recommend and I'll do the same" Nothing has changed.
May 29, 2009 4:00:21 AM

starams5 said:
You put it in quotes but I don't think you read what I said. "you recommend what you want to recommend and I'll do the same" Nothing has changed.

Sure, I'm not trying to argue with you, I'm just merely saying theres a lot of articles out there that are contradictory to what you are saying.
May 29, 2009 4:06:52 AM

I don't want to argue with you either g3force and I believe what you're saying about the articles. When I post, my comments come from something I have experienced and not something I read. This is where we differ here but no harm has been done.
May 29, 2009 4:28:02 AM

@croc

Online PSU calculator? You got to be joking, you might as well use a compass while your at it, it's probably more reliable.

Well fellows it's been fun chatting with you, we have severe thunder storm in progress so I'm shutting down before I need an upgrade myself. Peace always.
May 29, 2009 4:56:18 AM

starams5 said:
@croc

Online PSU calculator? You got to be joking, you might as well use a compass while your at it, it's probably more reliable.

Well fellows it's been fun chatting with you, we a severe thunder storm in progress so I'm shutting down before I need an upgrade myself. Peace always.


What? So worried about OP's psu, and yet you don't even have a decent UPS?

And BTW, my sailboat does have a compass, as well as a sextant and a good chronograph. One can't always count on electronics, so I keep in practice on my small voyages.

@OP: http://extreme.outervision.com/psucalculator.jsp
That's the underlying code that is used on most PSU sites that offer a calculator.

The best site for reviewing PSU's that I have found is jonnyguru.com.



May 29, 2009 5:12:52 AM

Your true colors came out croc. PSU calculator, you are an amateur at best and to think you had me fooled for a minute. And as far the sail boat is concerned, I have three, see how easy that was? And the link, who cares maybe you didn't read one of my previous post, I'll refresh your memory "my comments come from something I have experienced and not something I read." Next time direct your attention towards the OP, I didn't ask for your help or your advise and don't need it now. With that said, I'm not mad at you croc, never that.
May 29, 2009 5:43:46 AM

starams5 said:
Your true colors came out croc. PSU calculator, you are an amateur at best and to think you had me fooled for a minute. And as far the sail boat is concerned, I have three, see how easy that was? And the link, who cares maybe you didn't read one of my previous post, I'll refresh your memory "my comments come from something I have experienced and not something I read." Next time direct your attention towards the OP, I didn't ask for your help or your advise and don't need it now. With that said, I'm not mad at you croc, never that.


I think that my replies to you were more in the line of steering the OP clear of someone who does not really have the experience that they claim, advising them to get more PSU than they need without having all of the adequate facts at hand. That is the true definition of an amateur.

I'm not angry with you either, but I do wish that you'd stop advising posters to buy larger-than-needed PSU's just because 'you have personal experience'. I as well have 'personal experience', as well as access to a SunMoon PSU testing station. And the calculator that I linked is far more accurate than your 'guesstimates', backed up by many hours of testing. The Pro version is better, but the lite version will do you (or the OP) just fine.

Now go and buy a good UPS so you don't have to cower in fear of a wee thunderstorm....
May 29, 2009 5:57:31 AM

No coward here you pee wee, and what makes you think your advice is so special. UPS, it's just as easy for me to shut the computer down and get on the laptop, you keep trying to give me advice pee wee but nothing has changed, you have nothing to offer pee wee, your just another amateur poster, difference being you have an imaginary sailboat, I'm not mad at you croc.
May 29, 2009 8:45:36 AM

Sorry about not giving enough information.

Heres the specs of the PSU:

Power EBEL RB-400ATX

400 MHz,

3.3v (16a), 5v (25a), 12v (13a)
-5vsb (-2a), -5v (-0.3a), -12v (-0.8a)

Do you need the wire colours aswell, or is that enough information?

Also, I won't be running crossfire, as i'm just buying one card.
May 29, 2009 9:50:40 AM

magic_ghost said:
Sorry about not giving enough information.

Heres the specs of the PSU:

Power EBEL RB-400ATX

400 MHz,

3.3v (16a), 5v (25a), 12v (13a)
-5vsb (-2a), -5v (-0.3a), -12v (-0.8a)

Do you need the wire colours aswell, or is that enough information?

Also, I won't be running crossfire, as i'm just buying one card.


Your EBEL will be a tad bit suspect for what you want. I don't know what is available where you are, so I'll just throw out some suggestions. Any of the newer Antecs 450W or over will suffice, as well as any newer Corsair in the same range. Personally, I find PCP&C a tad bit overpriced here in AUS, but the same holds for them as well.

Look for 80+ certification, and a unit that incorporates active PFC that fits your budget. For your build, a good solid 14A should suffice on the +12VDC rails. If you want more PSU, I have already sent you the best links that I know of. Good luck, mate...
a c 243 ) Power supply
May 29, 2009 11:17:56 AM

magic_ghost said:


12v (13a)



A good quality 400 Watt ( not MHz ) psu such as the Corsair 400CX can provide 2.5 times the amount of 12v power and would certainly be powerful enough, your Ebel ( never heard of it ) will not.
May 29, 2009 1:54:22 PM

Thanks for all the replies. I've decided to go for a 750w PSU, since this will make the upgrade more future proof.
May 29, 2009 3:21:44 PM

Its best to post what PSU brand it is so people can advise on how reliable it is. Unless you have already gone by someones recommendation.
a b ) Power supply
May 29, 2009 8:41:34 PM

magic_ghost said:
Thanks for all the replies. I've decided to go for a 750w PSU, since this will make the upgrade more future proof.


If you're only using a single video card, a good quality 500W+ PSU is plenty. Corsair & Seasonic are good brands to choose from.
May 29, 2009 8:56:03 PM

500w would be sufficient, don't listen to starams5, i have a crossfire rig going with 650w, no problem
May 29, 2009 10:45:23 PM

mindless728 said:
500w would be sufficient, don't listen to starams5, i have a crossfire rig going with 650w, no problem



This guy don't know what he's talking about, he's on the leg. He just wants to be somebody's "Buddy". You made the right decision, he don't know what your plans are for your rig only you do.
May 30, 2009 12:00:06 AM

magic_ghost said:
Thanks for all the replies. I've decided to go for a 750w PSU, since this will make the upgrade more future proof.


What brand and model?

You do realise, I hope, that you will be on the lower end of any PSU's efficiency curve, right? And that your future upgrades would have to be in the nature of 2 x Nvidia 285's to even begin to use that much amperage?
May 31, 2009 4:51:15 PM

Ok, thanks again for the replies everyone.

It turns out that the 750w PSU I was going to get is out of stock, so i've bought the Corsair HX520w PSU instead.

May 31, 2009 5:04:46 PM

that's a good PSU, overpriced IMO since you could get a 650tx for about the same price but never the less a good PSU.
June 1, 2009 3:59:02 PM

Just out of interest, what is the effect on performance, if you use a PSU which is too powerful? Also, is there any danger of overloading the curcuits?
June 1, 2009 4:11:50 PM

Read this, I've had this for some time now:
--------------------------------------------------------------------------------------------

PSU efficiency data from SPCR review database.
The vertical scale has been truncated for clarity; please see text below for full discussion.

A system that draws ~250W maximum and idles at <100W would be a good match for the 300W PSU shown above.The efficiency power curve of the 600W PSU is better suited for a system than idles at >150W and peaks at >300W. It would be a substantially worse match for the system of the previous example, as the PSU would be operating at a mediocre <75% efficiency in idle, and only just reaching 80% at peak.

From a PSU heat waste point of view, the differences are significant:

At 200W load,

* the 300W model would generate 44W of heat (18% of 244W AC input);
* the 600W model would generate 50W of heat (20% of 250W AC input).

At 90W load,

* the 300W model would generate 23W of heat (20.5% of 113W AC input).
* the 600W model would generate 32W of heat (26% of 122W AC input).

Using the 600W PSU with this system is an example of incorrect, costly PSU sizing. It is practised most frequently by gaming enthsiasts who are encouraged to believe that greater power capacity is always better. Whether 480W, 550W or >600W PSUs are suitable for system that cannot possibly draw even 250W is a type of question asked almost daily in the SPCR Forums.

The counterpoint to "correct PSU sizing" comes from very high efficiency power supplies with very flat power efficiency curves. The models in the Seasonic S12 series, for example, differ so little in efficiency at the same 65~300W power levels that there's no real power consumption cost in choosing a high power model even if it is going to be used at lower power levels. With a system that only needs a maximum of 200W, the power consumption using a S12-500 or a S12-330 is essentially the same. Aside from the initial cost difference, there's no operational cost due to lower efficiency at lower power levels. With such power supplies, it makes sense to buy higher power capacity than currently needed in anticipation of future component upgrades that will demand more power.

EFFICIENT POWER SUPPLIES THAT DON'T START

Higher efficiency PSUs generally tend to need higher minimum power on the 12V line in order to simply run. Typically, we're talking about 1A or greater. Older, less efficient PSUs have much lower minumum current needs, under 0.5A and often ZERO.

In some recent motherboards, there are various time delays implemented in order to ensure that the PSU (and motherboard) is not subject to a huge current surge when everything turns on all at once. Many Asus boards have been identified as doing this, al though you won't get Asus to talk about it — I tried — they will say it's proprietary information they don't want to share with competitors. They are not the only board makers doing this.

The practice began during the peak of the Prescott era when startup surge became quite serious, but before the 80% efficient power supplies became common. Board makers extended the practice to AMD boards as well.


So this means, for example, that there could be anywhere between tens and hundreds of millseconds between different portions of the board and components being powered up. Just how much delay there is and how much power the CPU/VGA draw affects whether one of these high efficiency PSUs will actually start. Sometimes, adding HDDs will help, sometimes not — they may not pull current soon enough after the power button is pressed to change the current demand the PSU "senses". If the current sensor detects too low a load, the power supply usually does not start.

I don't have concrete information about the time delays involved. However, the Asus boards that would not start with some high efficiency Seasonic PSUs also would not start with some high efficiency PSUs from Antec, Fortron-Source, and Enhance.

A sure-fire way to tell whether too-low 12V start current is the problem is to hook up a known working, older, generic 300W PSU to the afflicted system. If max power was the problem, it would have a hard time starting, or not start at all. But invariably, with these too-low 12V start current situations, such PSUs (even several years old ones that long precede 24-pin ATX outputs, etc.) will start the system fine.

The reality is that most of the better brands like Seasonic and the others mentioned above are going for high efficiency because it is one of the big differentiators between PSUs today, and also very high power output. There are few PSUs that put less than 80% of the total power rating available on the 12V rail. For a 400W PSU, this typically means 320W is available on the 12V lines. You simply don't get a surge that big at startup with most computers, enthusiast or not, so even older PSUs should start fine on most systems

The upside of all this is that most PSU makers are aware of the issues here, and they are implementing solutions. The simplest one is to add just enough internal resistance on the 12V rail to ensure that there is enough current draw to start the PSU even with no 12V draw from the outside. This naturally drops the hard-earned efficiency down a notch, but it is in fact, what some PSU makers have done.

I know that Seasonic has quietly implemented an active circuit that automatically inserts enough of a load so that the 12V line always sees the minimum load, at least, but then this extra resistance is removed when the load gets higher, so that turn-on is never a problem, and high efficiency is maintained at normal and high power operation.

Which Seasonic models? I believe all the current sleeved output cable S12s, the S12-80+ models and the soon to come M12s.

POWER FACTOR CORRECTION

Increasingly, switched mode power supplies (SMPS) are designed with an active power factor correction (PFC) input stage. This is mainly to meet new regulations aimed at restricting the harmonic content of the load current drawn from power lines. Both users and power companies benefit from PFC, as does the environment.

Power Factor Correction (PFC) can be defined as the reduction of the harmonic content, and/or the aligning of the phase angle of incoming current so that it is in phase with the line voltage. Mathematically, Power Factor (PF) is equal to Real Power (Watts) divided by Apparent Power (Volt*Ampere). The basic concept is to make the input look like a pure resistor. Resistors have a power factor of 1 (unity). This allows the power distribution system to operate at maximum efficiency, which reduces energy consumption.

Non-PFC power supplies use a capacitive filter at the AC input. This results in rectification of the AC line, causes high peak currents at the crests of the AC voltage. These peak currents lead to excessive voltage drops in the wiring and imbalance problems in the three-phase power delivery system. The full energy potential of the AC line is not utilized. Nonlinear peak currents also distort output voltage and create harmonics. There is an international standard for controlling harmonics (IEC100-3-2) and PFC is mandatory for home appliances consuming 70W or more power in EU nations as of January, 2001.

PFC circuits are classified into two types: active and passive.

Passive PFC uses passive elements such as a ferrite core inductor on the input source to create a countering reactance. While easily applied to the existing power circuitry without much modification, the power factor is low (60 - 80%), the AC input must be chosen (115VAC / 230VAC), and the harmonics produced from the difference between the capacitance and the inductance are hard to control. Significant electromagnetic noise can result.

Active PFC uses switching regulator technology with active elements such as IC, FET and diodes, to create a PFC circuit This circuit has a theoretical power factor of over 95%, reduces total harmonics noticeably, and automatically adjusts for AC input voltage. However, it requires a complex EMI filter and an input source circuit, and is more costly to build.

The benefits of high PF for the user comes from the reduced AC current drawn by high PF PSUs, not in any savings from electricity bills, except in the case of commercial utility users who do pay for V(oltage) x A(mperes). There are two broad consequences:

Less stress on the AC electrical wiring: The lower current drawn by a high PF power supply means that there is less stress on the electrical wiring of the building. This can be a big plus in the case of older building with lower capacity AC wiring. It is certainly easy to see the benefits in a enterprise setting where dozens or hundreds of PCs are drawing power. If the total current load from the IT department could be reduced by 30% or more, this would be very signficant in direct electricity savings, reduced airconditioning cost, and possible avoidance of building AC re-wiring.

Lower UPS costs: Lower current draw also means that smaller capacity Uninterruptible Power Supply (UPS) units can be used. As UPS units are priced in direct proportion to their current capacity (VA), a PF of 0.98 versus one of 0.6 can traslate into a 40% reduction in purchase cost. Again, in an enterprise setting with hundreds or thousands of PCs, the savings can be very significant.


June 1, 2009 11:33:59 PM

starams5 said:
I say upgrade the PSU without a doubt. Just because a PSU will power your system don't necessarily mean its okay. Being under powered can be associated with many problems including early parts failure especially HDD's. The AMD 790GX chipset supports Crossfire X at a reduced bandwidth rate so I'll give you two good options.

Without CF:
http://www.newegg.com/Product/ProductList.aspx?Submit=E...

With CF:
http://www.newegg.com/Product/ProductList.aspx?Submit=E...

Note: The 850w may be a bit overkill but I like overkill, you would probably be okay with a 750w PSU.


Actually a quality 400 watt unit would be fine, although 500 watts would probably be more ideal, given that there are enough amps on the 12v rail(s).
TH was able to SLI 8800GT's and an overclocked C2D on a 400-watt... perfectly stable, although the power supply was a silverstone model (good :])
June 2, 2009 12:21:20 AM

doomsdaydave11 said:
Actually a quality 400 watt unit would be fine, although 500 watts would probably be more ideal, given that there are enough amps on the 12v rail(s).
TH was able to SLI 8800GT's and an overclocked C2D on a 400-watt... perfectly stable, although the power supply was a silverstone model (good :])


You need to stop drinking.
June 2, 2009 1:17:13 AM

so just out of curiosity, what would an oced phenom 2, say 30% and 2 4890s draw @ load?
June 2, 2009 4:58:13 AM

starams5 said:
You need to stop drinking.

Um. Yea.

Think before speaking. Did you even read the article you posted?
http://www.tomshardware.com/reviews/System-Builder-Mara...
Seriously, at full draw, my system uses maybe 300-watts.
If you still don't believe me, go to jonnyguru.com, ask the same question; refer them to this thread.

As I said before. A quality 400 watt would be more then enough. I stress QUALITY. Not QUANTITY. The unit he has would most likely be a bad idea.
June 2, 2009 5:12:13 AM

doomsdaydave11 said:
Um. Yea.

Think before speaking. Did you even read the article you posted?
http://www.tomshardware.com/reviews/System-Builder-Mara...
Seriously, at full draw, my system uses maybe 300-watts.
If you still don't believe me, go to jonnyguru.com, ask the same question; refer them to this thread.

As I said before. A quality 400 watt would be more then enough. I stress QUALITY. Not QUANTITY. The unit he has would most likely be a bad idea.


Please don't feed the trolls....
June 2, 2009 5:30:52 AM

@crac
I thought you were afraid to come out and play pee wee. I took you for being gay anyway.


@Rockin
I'll be serious too. I'm not trying to change how you feel about these smaller unit's one way or the other. You have your experiences with these smaller unit's and I have mine, quality not quantity. See most of the small "quantity" PSU won't even post a system with decent specs. Then on the other hand the small "quality" units will post and run the system, or so you think. A couple months down the road you lose a HDD. No problem, RMA it and get another one. Before the year is out something else fails maybe even another HDD, but the small "quality" PSU is still running just fine. To make a long story short, never send a boy to do a mans job. The Op said he has plans for upgrading his system and you recommend a 400w PSU. He may have plans for water cooling, more HDD's, Blue-Ray, or CF, read his first post. What can he possibly do with a 400w PSU but buy another PSU the next time he wants to upgrade. Even a small "quality" PSU can only take so much, eventially upgrades will take them down quality or quantity.

http://vip.asus.com/forum/view.aspx?id=2009021122382978...


http://vip.asus.com/forum/view.aspx?id=2009022403292186...
June 2, 2009 5:59:53 AM

starams5 said:
@crac
I thought you were afraid to come out and play pee wee. I took you for being gay anyway.


@Rockin
I'll be serious too. I'm not trying to change how you feel about these smaller unit's one way or the other. You have your experiences with these smaller unit's and I have mine, quality not quantity. See most of the small "quantity" PSU won't even post a system with decent specs. Then on the other hand the small "quality" units will post and run the system, or so you think. A couple months down the road you lose a HDD. No problem, RMA it and get another one. Before the year is out something else fails maybe even another HDD, but the small "quality" PSU is still running just fine. To make a long story short, never send a boy to do a mans job. The Op said he has plans for upgrading his system and you recommend a 400w PSU. He may have plans for water cooling, more HDD's, Blue-Ray, or CF, read his first post. What can he possibly do with a 400w PSU but buy another PSU the next time he wants to upgrade. Even a small "quality" PSU can only take so much, eventially upgrades will take them down quality or quantity.

http://vip.asus.com/forum/view.aspx?id=2009021122382978...


http://vip.asus.com/forum/view.aspx?id=2009022403292186...

Do you read anything? I recommended a 500-watt power supply.
All I said was a quality 400-watt would run his current setup fine.
June 2, 2009 6:06:08 AM

@Rockin

You see that's the whole problem here we tend to see what we want to see because I said this:

"He may have plans for water cooling, more HDD's, Blue-Ray, or CF, read his first post."



June 2, 2009 6:09:16 AM

starams5 said:
@Rockin

You see that's the whole problem here we tend to see what we want to see because I said this:

"He may have plans for water cooling, more HDD's, Blue-Ray, or CF, read his first post."


Eh, which is why the link I posted was to a good 500-watt.

This is on a road to nowhere.
June 2, 2009 6:13:16 AM

"This is on a road to nowhere."

I agree, I knew that when I said this "I'm not trying to change how you feel about these smaller unit's one way or the other. You have your experiences with these smaller unit's and I have mine, quality not quantity."

No hard feeling here and I hope you feel the same.
June 2, 2009 3:39:13 PM

Well I think that's my question answered. Thanks again for all the replies. Much appreciated.
June 2, 2009 5:57:57 PM

magic_ghost said:
Well I think that's my question answered. Thanks again for all the replies. Much appreciated.

haha. It's good that you were able to get some usable information out of me and starams' bickering.

No hard feelings staram :) 
!