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Dumb question about CPU power cable

tabascosauz

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There's a lot is speculation that plugging in the second 8-pin will magically improve ______ performance, outside of providing extra wattage when >300W. I haven't seen any difference on my Unify-X, and I highly doubt any board makers are designing their boards in a way that might make a difference (hello ASRock and cost-cutting). Not seen any evidence anywhere else either.

In any case, Ryzen boost is now so variable from run to run and day to day that there's basically no way to get reliable results. And there should be absolutely no reason for it to affect LLC in any appreciable way.

And software sensors for PSU rail voltages are only very broadly indicative of anything (ie. 9.5v on 12v rail), so how are you supposed to back up a statement like that?
 
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qubit

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It's a top quality Seasonic PSU on a fairly high end board, I'm not concerned. I just wanted to know if the limit was above 150W and I got my answer several times. It's 336W.
To be honest, I think you’ll be alright. The principle of doubling up is sound though. And yeah, +1 on Seasonic.
 
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extra cables, problems with top fan mounting (for example my new H510 Flow can not mount a 140mm in the top with the second 8 pin plugged it. without it it fits just fine)
there is just no reason to do this except for running P95 with ice water cooled 12900ks or similar.
If you have setup issues like this I can understand, esp if what you have is what you've got to work with and have nothing available to change it to such as a different fan from the 140mm for example.

As for a reason based on "No reason to do this except for running P95 with ice water cooled 12900ks or similar" is really not true.
Starving a component for power is just as bad if not worse than giving it a bit too much based on what it's calling for.

Lack of power can make things run hotter, an example of it is when you have a weak battery in your auto and you try starting it a few times - The starter motor will get super hot, super quick because the battery is too weak to supply what it needs to function properly.

Once power is induced into the circuit it has to go somewhere and it will. In this case instead of it being converted into motion it instead becomes and is forced to dissapate itself as heat through the device in question - Which obviously affects the device itself.

The only exception of this is a battery or capacitor or a similar device that's made to absorb and hold/store such energy.
Things like chips and motors cannot store this energy, that's why it must dissapate and is not stored or kept.

Also - Like the starter, the chip is an electrical device and operates under the same basic rules of how electricity works, you can't change that fact of it.

And like any other electrical device heat is an enemy to it, probrably the worst enemy it has to contend with anyway so keeping it cooler with such a setup is only helping it anyway.

I'm lazy and if the second EPS is 4pin, I just don't bother. That and if I know I'll be under 300~ CPU load, I simply do not care enough.
And any problems as a result are on you but at least you're honest enough to admit it.

Thing is the plug/header is there for a reason.
To me it doesn't make sense not to use it if you can, so any problems over what the thread is about are taken care of before there is a problem in the first place.
 
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Probrably, but had to back up what I was getting at and say why.
Over and out on this one.
 
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As others have kinda said:

4 pin will boot anything out there
8 pin is needed for high wattage chips, like modern intel
12 pin is for extreme use

Basically, if you have 8 pin in there right now it's perfectly fine - but next time you rebuild the system, add the extra in. It's a small little extra bit of longevity for no effort, that way.
 
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As others have kinda said:

4 pin will boot anything out there
8 pin is needed for high wattage chips, like modern intel
12 pin is for extreme use

Basically, if you have 8 pin in there right now it's perfectly fine - but next time you rebuild the system, add the extra in. It's a small little extra bit of longevity for no effort, that way.
Sure will, don't see why not. Doing it right now is a PITA due to the top mounted fan.
 
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