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How to know which rail in PSU powers what connections?

It was, as you said, 'back in teh day' (and Im thinking with crap PSUs...). Never had an issue with voltage sagging on the 12v with a single rail PSU. Never. I buy quality PSUs and/or must be lucky? Did so since 2004 when I really got into things. :)

ATX spec is 5% (11.4v to 12.6). So long as it is within that range, your PC should be all good anyway (that is why motherboards/GPUs have their own power delivery area to further smooth things out and step the voltage down etc). Of course, less fluctuation is better as there is less 'stress' on other components, particularly when overclocking at the limits. But the point remains. This isn't a problem to worry about these days regardless if it is a 'true' multi-rail PSU (internals) or just done by OCP (also internally handled).
 
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This question is why having a PSU with a single 12v rail is best.... no confusion as to which connection draws from where.
 
EarthDog said:
I personally run my PSU's around the 80% level of its capacity. I lose 1% or so by not running it around 50%, but I also didn't overbuy.
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I'd feel better running it at 50% because two reasons ... I often "forget" to clean dust filter on the bottom of the case :oops: and because of the PSU capacitors aging. My Corsair 650 TX is 5 years old and I doubt it can push full 650 watts anymore.
 
QUALITY PSUs are good/tested to 40-50C intake temps (will vary on model)... if your ambient is 20-25C or so, I surely wouldn't worry about dust on the filter and the PSU warming up.

I bet it could still output 650W... while capacitor aging is certainly not a myth, it, like the wattage needed, has been blown out of proportion.

Think about it... how are companies making 10 year warranties on their PSUs if they can't output their label power after that time? 5 years? It all depends on the QUALITY of the internals used. I have a Seasonic 1KW Platinum that is four years old and it will happily put out 1KW and more. Now, the low end TX line from corsair may be a different story... but my statements should be taken under the context of a QUALITY (read: Tier 1) PSU.

I even asked Oklahoma Wolf of JGuru fame about running a PSU at its rated wattage for the life of the warranty. He responded that it damn well should.. if its a good PSU.
 
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Why wouldn't a good unit do it? They will have high quality solid caps. So while degradation is a thing, it shouldn't happen that fast.

I have had this unit with its fast as hell racing stripes for a while. I strongly doubt even the efficiency has dropped and if anything has been proven it is that racing stripes make things faster.
 
EarthDog said:
I bet it could still output 650W...
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Sure it can, with more ripple and worse voltage regulation ... max output doesn't suffer, but system gets less stable at high loads ...
I definitely agree effects and speed of degradation are blown out of proportion, but that depends on operating temperature combined with capacitors quality.
EarthDog said:
Now, the low end TX line from corsair may be a different story... but my statements should be taken under the context of a QUALITY (read: Tier 1) PSU.
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Corsairs TX v2 series are made by Seasonic (but still lower tier 80 gold).
Yeah, it really is all about context ... having Tier 1 PSU + willing to test its limits and having lower tier + not willing to risk it.
I'm really curious now how long will it last ... it hasn't seen a load over 400W in these 5 years :laugh:
 
BiggieShady said:
Sure it can, with more ripple and worse voltage regulation ... max output doesn't suffer, but system gets less stable at high loads ...
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LOL, NOW you clarify you were not talking max wattage...

I also didn't click to see v2... which is only in your specs, not what you posted.

Yeah, I would bet good money says that V2 will run 650W with things in spec not affecting overclocks...
 
Mine has caps on the connectors I would bet I am well within ATX spec still. Powercache its not just a gimmick haha
 
EarthDog said:
LOL, NOW you clarify you were not talking max wattage...
I also didn't click to see v2... which is only in your specs, not what you posted.
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Yes, I clarify things as I go after a long day at work lol ... I should have said "I doubt it can push full clean 650 watts anymore."
EarthDog said:
Yeah, I would bet good money says that V2 will run 650W with things in spec not affecting overclocks...
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I'd like to visit that kind of a gambling establisment also
 
You would lose in this case... sorry.

But let me clarify... there may be more ripple, etc, but not to the point where it will affect ambient cooled overclocks. So to me, its a moot point.
 
EarthDog said:
You would lose in this case... sorry.
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I never said I'd take your bet, so sorry back at ya.
EarthDog said:
But let me clarify...
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Your point was never unclear ... good PSU is inside ATX spec at 50C ambient at 100% load even after 5 years ... but we can agree it won't last forever, fan will die first and when that happens in the middle of gaming session, at 50% load it will survive long enough until I notice fan died and replace it.
 
Those fans must be loud!

...in other news, I've never heard my psu fan when it's inside my case. :)
 
EarthDog said:
Those fans must be loud!

...in other news, I've never heard my psu fan when it's inside my case. :)
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That's because you apparently never had a properly quiet PC. The last time I had a loud PC was back in 2001 when I had my Athlon 1GHz cooled by Thermaltake Dragon Orb cooler. The thing was so damn loud I decided to go silent at any cost. When you have to look at PC indicator lights to know if it's on or not (when screen goes off), then you've achieved the goal. And trust me, you can hear the PSU. It doesn't even have to be the airflow noise, in my case it was super annoying clicking of the fan and when something is doing that, it'll drive me insane. It's the whole reason why I went and replaced the shitty ball bearing fan with a FDB fan from Noiseblocker in my former Corsair HX750. After that, it was whisper quiet with no repeating clicking noises or cycling vibrations. And one of the reasons why I've opted for Be Quiet!, because it already had a quality fan in it, so I don't have to void the warranty.
 
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RejZoR said:
That's because you apparently never had a properly quiet PC.
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I'm not sure you could be any more wrong about that. ;)

BiggieShady said:
but we can agree it won't last forever, fan will die first
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Yes. It wont last forever...

And with many PSUs a lot of their fans don't kick on until a certain load/temp so their hours are a lot less than one that constantly runs.. so I wouldn't bet on the fan being the first thing to crap out. The TX v2 line does that in fact.
 
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On digital units, the passive mode is pretty much useless, because it's set so low...
 
On some maybe... but look around, the set points are at different temps/loads or handled by a switch in some cases.
 
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