Are the 3.3V and 5V rail important?

[Ian]

Which PSU for my A64 system? Plus some other questions...

Just completed an upgrade from a Socket A system and current system is listed in signature below. I'm still using the Fortron 530W from my older system and read that it could be a problem (DFI needs native 24pin PSU and a higher rating on 12V rail), though it is still running fine with a 20pin to 24pin adapter. Not sure if it's the PSU though but I'm experiencing some lockup in games and 3DMark even at stock speed and somehow my Venice isn't overclocking too great (only 2.4GHz ) so I'm hoping that a new PSU will do me good.

So I was told I will need a newer PSU for my A64, especially since they run off the 12V rail and I will be overclocking. Now looking at the Fortron AX500-A which seem to be highly recommended at its price range both in this forum and over at DFI-Street.

While doing a search online, I've also came across an Enermax Liberty 400W which costs about the same as Fortron AX500-A.


Fortron AX500-A = 30@3V, 28@5V, 15@12V1, 15@12V2 (??A combined)
Enermax Liberty 400W = 26@3V 26@5V 20@12V1, 20@12V2 (30A combined)


I'm debating myself whether to get the Enermax over the Fortron because of the stronger 12V rail, sacrificing for the lower 3.3V and 5V rail on Enermax? Please advice.


EDIT: Changed the title to better reflect the nature of this discussion.

 

[Oklahoma Wolf]

You're not gaining anything with the Liberty over the AX500-A - the combined 12v power is the same. You'd actually have to go to the 620W to find a unit more powerful on the combined 12v. In addition, Fortron's build quality I find to be substantially better.

I came very close to getting the AX500-A for my upcoming DFI board as an upgrade to my own FSP530-60GNA. I knew the 530W wouldn't like the new build, so it had to be upgraded. Ultimately, I ended up with the FSP600-80GLC since it had active PFC instead of the AX500-A's passive. Unfortunately, not being the Epsilon version of the unit, I didn't get PCI-E connectors so I have to solder them in there.

Since you're in Hong Kong, it might be worth it to try and find Fortron's 460W Green Power units (can also be found as the Zalman 460W). These are better designs than the AX500-A... higher efficiency with active PFC. Give Seasonic and Delta a look too if you can find them over there.

 

[larrymoencurly]

I just got an ECS nForce3-A mobo and Sempron 2800+, and while running MemTest86 I measured 4.8A @ +3.3V, 0.4A @ +5.0V, and 2.0A @ +12V. This was with almost nothing else but a floppy drive and slow PCI graphics card. One capacitor on the mobo runs really hot, > 60 Celcius, probably because of absorbing heat from the 90C MOSFET right next to it. Definitely heatsink time.

 

[Ian]

You're not gaining anything with the Liberty over the AX500-A - the combined 12v power is the same. You'd actually have to go to the 620W to find a unit more powerful on the combined 12v. In addition, Fortron's build quality I find to be substantially better.

So the 12V combined output is just a simple summation of 12V1 and 12V2? Because the rating from Enermax doesn't seem to agree with this (20A for both 12V1 and 12V2 but 30A combined).

Also I looked at the spec sheet for the AX500-A but can't find a rating for the combined output. I'm not sure if this is correct but here is the calculation that 12V combined output is (445-160)/12 = 23.75A.

I came very close to getting the AX500-A for my upcoming DFI board as an upgrade to my own FSP530-60GNA. I knew the 530W wouldn't like the new build, so it had to be upgraded. Ultimately, I ended up with the FSP600-80GLC since it had active PFC instead of the AX500-A's passive. Unfortunately, not being the Epsilon version of the unit, I didn't get PCI-E connectors so I have to solder them in there.

OK, so I shall make sure my new PSU must have active PFC rather than passive PFC. I wasn't too sure about all this active Vs passic PFC thing, only knowing that active PFC are more efficiency

Since you're in Hong Kong, it might be worth it to try and find Fortron's 460W Green Power units (can also be found as the Zalman 460W). These are better designs than the AX500-A... higher efficiency with active PFC. Give Seasonic and Delta a look too if you can find them over there.

Is this what you are referring to? Can't seem to find another 460W from Fortron. This one costs more than the AX500-A though.

Seasonic is not available in Hong Kong if I'm not mistaken. Brands of quality PSU available in Hong Kong are SPI (Fortron), Antec, Delta, Enermax, Coolermaster, Tagan, 2themax (rebadged Topower), etc...

I'm also considering a 2themax 420W (link) which seem to be in the same series as the OCZ PowerStream, though not as beefy as the OCZ PowerStream 520W.

 

[Know Nuttin]

So the 12V combined output is just a simple summation of 12V1 and 12V2? Because the rating from Enermax doesn't seem to agree with this (20A for both 12V1 and 12V2 but 30A combined).

No, it's not always that way. Some units can do the max output on both at the same time. Other's cannot and just state the max that each one can do individually but not concurrent.

Also I looked at the spec sheet for the AX500-A but can't find a rating for the combined output. I'm not sure if this is correct but here is the calculation that 12V combined output is (445-160)/12 = 23.75A.

The AX500-A is able to output the full 15 + 15A on the +12v rails. It's probably closer to 18A, as this unit is generally underrated.

Seasonic is not available in Hong Kong if I'm not mistaken. Brands of quality PSU available in Hong Kong are SPI (Fortron), Antec, Delta, Enermax, Coolermaster, Tagan, 2themax (rebadged Topower), etc...

Depending on which version of the Delta you are looking for, I would go with them first, followed by Fortron/SPI.

 

[Oklahoma Wolf]

So the 12V combined output is just a simple summation of 12V1 and 12V2? Because the rating from Enermax doesn't seem to agree with this (20A for both 12V1 and 12V2 but 30A combined).

On the Fortron, yes. On the Enermax, no. The Fortron is designed to be able to meet the full 15A spec on both rails. IIRC there is a peak number given for them too, but I just go by what's on the spec sheet for it.

Also I looked at the spec sheet for the AX500-A but can't find a rating for the combined output. I'm not sure if this is correct but here is the calculation that 12V combined output is (445-160)/12 = 23.75A.

As I mentioned, there is no combined 12v rating for this one - it can do the full 15+15 as long as the combined 3.3v/5v rating is not being stressed. There is a combined 12v rating for the AX450-PN and AX400-PN however... these two are closer to Enermax' rating system (which has always been overly optimistic).

OK, so I shall make sure my new PSU must have active PFC rather than passive PFC. I wasn't too sure about all this active Vs passic PFC thing, only knowing that active PFC are more efficiency

Is this what you are referring to? Can't seem to find another 460W from Fortron. This one costs more than the AX500-A though.

Active PFC would be a very good idea for HK, where you might be billed for apparent power

That 460W is superior to the AX500-A - it's a server unit with independant voltage regulation. These are older designs that are less efficient, but built like tanks. They are direct competitors to the OCZ Powerstreams.

The 460W Green Power is this one: http://www.fsp-group.com.tw/english/1_product/2_detail.asp?mainid=1&fid=52&proid=301

It's not available yet in North America to my knowledge as anything other than Zalman's new 460W unit.

I'm also considering a 2themax 420W (link) which seem to be in the same series as the OCZ PowerStream, though not as beefy as the OCZ PowerStream 520W.

That does bear a striking resemblance to the Topower TOP-526P6, aka OCZ Powerstream 420W. Can't say for sure that it is one, as I haven't been able to find innards pics, but that does look to be a good PSU.

Edit - I'm now 95% sure it's a P6, since 2themax has it listed under the Tagan section. Tagan is exclusively Topower.

 

[Ian]

Depending on which version of the Delta you are looking for, I would go with them first, followed by Fortron/SPI.

There is a Delta "Active Power" 460W (GPS-460BA-102 B) available in Hong Kong, can only find the information in Delta's China site: http://dgeservice.deltadg.com.cn/diy/product_660.asp

It has active PFC and is rated at: 30A @ 3.3V, 28A @ 5V, 14A @ 12V1, 15A @ 12V2. Cheaper than the AX500-A but less 1A on the 12V2 rail.

 

[Oklahoma Wolf]

That would be a very good alternative to the AX500-A that would do well with your system. I consider Delta build quality to be superior to Fortron, Enermax, and Topower - I expect it would last you for several years. It is the 12v2 rail that will be powering the CPU, but unless you're planning on a Prescott 15A should be plenty. It's rated in a similar fashion as the AX500-A... IOW, it's good for full power on both 12v rails at the same time as long as the combined 3.3v/5v draw is low (and it will be on your system).

 

[Ian]

The Maxpower series from 2themax has always been rebadged Topower, that's what I've been seeing. There's a close resemblence between the ratings, model name of the 2themax and Topower PSU's.

I suppose you're searching for '2themax & tagan' in google right? I think Tagan was originally sold by 2themax before, but is no longer the case now. Another company (GTR or Genteelord) has take over the role.

 

[Oklahoma Wolf]

Cool - at any rate, the way those PSU's are named plus the identical specs do lead me to believe those are indeed Topower P6 units. You'd do very well with that 420W I think, though it likely won't live as long as the Delta.

Interesting thing is, they still list the 580W P6 - it's never even appeared on the Topower site. That 470W might be the best of the lot though - the OCZ version did very well when tested at Xbit before it was discontinued by OCZ.

 

[Ian]

Some more questions:

Is single rail better than dual rail for the 12V? I've been reading in forums and people seem to prefer single rail rather than the dual rail which is required for the latest ATX2.x specification?

Regarding the Active Vs Passive PFC, the former one will have a higher efficiency and a power factor close to one. Here comes the question, what does the latter one mean? Let's say we have an Active PFC and a Passive one with similar efficiency but different power factor, does it make any difference?

Concerning the "individual voltage regulation", is it the individual rails (independent +3.3V, +5V and +12V) which brought about by Antec (CWT/Channelwell)? Shall it be a 'must-have' for my PSU as I read the rails will be independent on each other so if you overload the +12V rail, the +3.3/+5V won't be affected. However with the newer PSU's all shifting the output to the +12V rail and lesser on the +3.3/+5V rail, is it still necessary?

 

[Oklahoma Wolf]

Some more questions:

Is single rail better than dual rail for the 12V? I've been reading in forums and people seem to prefer single rail rather than the dual rail which is required for the latest ATX2.x specification?

If you're overclocking an Intel CPU, have more than one CPU, or are running SLI with a lot of drives a single 12v unit (or a quad in some cases) would be preferable. Otherwise, it's not too big a deal.

Regarding the Active Vs Passive PFC, the former one will have a higher efficiency and a power factor close to one. Here comes the question, what does the latter one mean? Let's say we have an Active PFC and a Passive one with similar efficiency but different power factor, does it make any difference?

PFC actually decreases efficiency - its function is to basically decrease the load apparent to the utility. It's required in Europe, where people are billed for apparent power.

Concerning the "individual voltage regulation", is it the individual rails (independent +3.3V, +5V and +12V) which brought about by Antec (CWT/Channelwell)? Shall it be a 'must-have' for my PSU as I read the rails will be independent on each other so if you overload the +12V rail, the +3.3/+5V won't be affected. However with the newer PSU's all shifting the output to the +12V rail and lesser on the +3.3/+5V rail, is it still necessary?

Channel Well wasn't the first to implement this sort of thing - I know at least Fortron was ahead of them by a few years with their EPS models. It's not really a must have, but preferable - these usually hold the rails tighter than cheaper non independant designs. That 2themax unit will have independant voltage regulation. Many Enermax units do as well, but I'm not sure about the Libertys. The Fortron AX500-A doesn't - the current Fortron models that do are: FSP550-60PLG, FSP550-60PLN, FSP550PLG-SLI, FSP460-60PFN (the one you mentioned before), and the Zen fanless models.

 

[Ian]

Currently looking at Antec PSU's, I will look into other manufacturers later, there're simply too many choices and I'm very confused!!!

I'm planning to get one that costs about USD80 and can power my current system (in sig) as well as my future upgrade which will probably be some dual-core s939 and a better display card. I DO overclock and I'll most probably stay with AMD but I don't plan on running SLI yet. If I have the money to go SLI, I might as well replace the PSU as well.

Antec TPII-480

• 18A on 12V1, 18A on 12V2, no info on combined 12V
• single 120mm fan
• individual voltage regulation
• can't find the type of PFC

Antec NeoHE 430

• 16A on 12V1, 12V2 and 12V3, 32A combined
• one 80mm fan
• not sure if it has individual voltage regulation
• very high efficiency on paper, with Active PFC

Antec SmartPower 2.0 500W

• 17A on 12V1, 19A on 12V2, no info on combined 12V
• two 80mm fan
• not sure if it has individual voltage regulation
• can't find the type of PFC

NeoHE 430 has pretty good efficiency (over-rated?) and 32A combined +12V output which is on-par with the Fortron AX500-A which I've been eyeing. However, there's no info on the individual voltage regulation which TPII-480 features. Is it 36A combined +12V output for the TPII-480 as it boasts individual voltage regulation?

The former two costs the same while the SmartPower is slightly cheaper so I'm including it in here.

Later...

 

[Oklahoma Wolf]

The Neo HE's do have independant voltage regulation, but unlike other Antec models are OEM Seasonic rather than CWT. They're good as long as you don't have certain incompatible Asus boards to run with them.

CWT designs like the Truepower 2's are usually good for the full output on the labels. They're rated more or less honestly, except the rating is given at a low 25 degrees. The Smartpowers will not have independant regulation, but the True 2's do.

 

[Ian]

Seems that the Smartpowers are off my list then because of the lack of individual rails.

Which Seasonic series is the NeoHE based on? Because I'm seeing 3 seperate +12V rails on the NeoHE's but only 2 seperate +12 rails on the Seasonic S12. I'm hoping they're rebadged S12's as I've been reading how quiet these units run!!!

 

[Oklahoma Wolf]

They're custom built for Antec - Seasonic has no equivalent at the moment. The S12's are superior build quality however and are still independantly regulated IIRC. I've seen reports that the HE's really only have two 12v rails, but I haven't confirmed that rumor yet.

 

[Ian]

They're custom built for Antec - Seasonic has no equivalent at the moment. The S12's are superior build quality however and are still independantly regulated IIRC. I've seen reports that the HE's really only have two 12v rails, but I haven't confirmed that rumor yet.

I won't be considering the NeoHE's as I heard there're compatibility problems with some motherboards, not sure if it's been sorted out yet. The NeoHE 430 review over at SilenPCReview is also saying that the NeoHE could be a dual-rail PSU.

I just got a DMM this afternoon and the 12V on my Fortron 530W is 11.55V idle and 11.48V under load. Time for a new PSU....

Will you recommend the Delta ServerPower 460W (GPS-460BA-120 A)? I can get it for $59 here. Do you think it is good enough even if I go dual-core later?

I can't find any reviews on the net, most probably because this PSU is currently for sell in China and Hong Kong only. It is rated for 14A@12V1 and 15A@12V2, no info on the combined 12V output so I'm assuming it is 29A? It has Active PFC but the rated efficiency is pretty low at 70%.

One of the 'review' (last link below) says that it has individual voltage regulation, can you tell by looking at the PSU interior?

Spec
http://dgeservice.deltadg.com.cn/diy/product_660.asp
http://dgeservice.deltadg.com.cn/diy/power0705/Deltapower -HK.htm

Reviews (in chinese but they got some good photos of the unit)
http://power.zol.com.cn/2005/0422/165881.shtml
http://publish.it168.com/2005/0420/20050420509101.shtml?cChanNel=09&cPositionCode=396
http://www.hkepc.com/product/psu/sp460-delta.htm

Also, I saw in your other post that the rated temperature is also important as performance degrades with increasing temperatures. Some manufacturers are exaggerating the output with 25C while some others are being honest to rate at 50C. Where do I usually find this information? I saw that Fortron has it listed in all of the spec sheets. But what about the others? e.g. Antec PSU's are listed with an "operating temperature" of 10C~50C, does it mean that the rating is given at 50C?

Thank you!

 

[Oklahoma Wolf]

That Delta will do perfectly - I believe it does have independant regulation, but the pics aren't quite good enough to be totally sure. Delta build quality IMO is a little better than Fortron btw - I can't see you not liking it

I don't know what temps Delta rates these at, but I'm willing to believe they're rated better than most. 40 degrees most likely. Fortron's usually pretty forthcoming with their ratings in the spec sheets... I found out to my delight a few days ago my new 600W is rated at 50 degrees

Antec does not specify a temp except in the case of the Neo HE (50 degrees), but their Channel Well built units (everything but the Neo HE) are all at 25 degrees (except the Phantom maybe). Among the other high end brands Zippy is at 40 degrees, Etasis at 50, Win-Tact at 50 (PC P&C 510W, 850W, 1kW), Seasonic at 40. Finding this info can be difficult - in Antec's case, you need to go to CWT's website where only a few of them have the temp specified.

 

[Ian]

It says "-12V, -5V, +3.3V, +5Vsb individual output", argh, so it seems that the individual regulation isn't in place for the +5V and +12V which will be used most? Dammit...

On the other hand, this label comes from a unit sold in the Chinese market while the attached photo which my friend has taken of his new Delta 460W bought in Hong Kong, notice the difference between the combined output of 3.3/5/12 is 410W Vs 445W

 

[Oklahoma Wolf]

They appear to be two different versions of the same model:

GPS-460BA-102A
GPS-460BA-102B

I have no idea what the differences are, but they both look strong enough to power your system.