Juular

-5V rail, depending on how ancient your S12II it may still have one. PSUs for ATX 2.0 and past don't have one. One of your GPUs uses said rail, the other doesn't,

That's not the reason why it's bad, it's bad because Seasonic didn't make sure that it's good. As you can outsource a product but make sure that it's good, control what's the OEM is doing, make sure it's competitive, just as you can just grab whatever cheapo off-the-shelf stuff and sell it only based on your brand recognition, like Seasonic did. Mind you, speaking of Powerspec / Microcenter i don't really have faith in them making sure that these PSUs are actually good, in having control over their OEM (Sirfa / High Power in this case), but it's way further from being a bomb than Seasonic S12III.

1. As long as it's still under warranty, but generally speaking after 8 years or so you should question whether you value the hardware you're powering with it or not, if yes - replace it even if it's still under warranty. PSU warranties are more marketing than anything, they're determined based on multiple factors including an assumption of 'average use case', if your specific use case is more heavy than on average - your PSU may fail earlier, but it doesn't always work the other way around unless you actively maintain the PSU (replacing TIM on power components for example, because it dries up just as much as on CPU/GPU and power silicon doesn't like overheating), but then you lose the warranty. 2. None unless you have specialized testing equipment and know how to operate it. 3. Depends, if a system is really old (like i guess around Pentium II/III ara) it may still need -5V rail none of modern PSUs have. Don't see the problem in your PSUs failing after 9-13 years, that's actually great but thing is, a PSU failing completely doesn't mean it was working good before that. Ripple and transient response may have been worsening silently over the years and slowly killing your components. As of PSU recommendations, it's not about the brands, no such thing as 'high-end' brand you can just grab whatever model even if it's 80+ Gold/Platinum/Unobtanium. It's about specific models, and there's a PSU tier list for that which i'm sure you can google (the one hosted here is outdated). Generally speaking Corsair RM/RMx or HX if you're feeling fancy would be the best options, EVGA G6 if cheaper, but there are a lot of other good picks if even cheaper than that.

If you're trying to future-proof a PSU you shouldn't buy a budget one, just doesn't make sense. Either get a best 550W for your budget and current build if you're short on money or spend more and buy an actually good 650/750W for future-proofing.

It's almost like the tier list specifies what the exact label color for each variation of Antec pick-a-new-random-color-for-the-same-series PSUs you should be looking at. There were no green/lime label Atom B at the time of the last update but at this point i contemplate just lumping them all together into just 'Atom' without any specifics, they're all near junk anyway with zero reviews.

It's almost like replacing a PSUs fan for random one, especially in one of the most complex consumer PSUs on the market is not the brightest of ideas. It's not supposed to work with whatever fan you throw at it, and it doesn't know that it's trying to drive a different fan, that's why the fan isn't spinning when it should and that's why it doesn't increased RPMs, because it knows it should use specific RPM at specific component temperatures. I don't know if it's supposed to ramp up the RPM to maximum as a failsafe to try to cool itself at temperatures past what it's supposed to work with but below OTP threshold, but at this point it doesn't matter. Solder the old fan in, sell the thing, buy a new quiet PSU if you want one.

Seasonic S12III is garbage. Corsair CX-m is fine but probably not worth it over be quiet! System Power 9U with this price difference and for this build. Try to find Corsair CV650, if it's same price as U9 it would be preferable, 650/750W versions of it are different than 450/550W.

Because it's under the glue. If you're sure that the smell is coming from the PSU then just replace it.

You're thinking of a different varistor. Metal-oxide varistor (MOV), which is the part of transient filter is indeed desiged as sacrificial element in protecting the PSU from high voltage spikes coming from the mains, it's not related to OVP tho, and no one calls them variable resistor. In this case this is a variable resistor or potentiometer or rheostat, but it's not varistor, similar terms but completely different components, hence the confusion. And the glue is there to fix the setting it was set to at the factory, so more appropriate term would be 'adjustable' in this case, since it's set once and forget application. The smell could potentially be coming from the said glue if it gets hot enough but idk, might be something different or not even related to the PSU. Are the PSU side connectors/terminals and the cables look alright ? No melted stuff, no charring ? Paging @jonnyGURUjust in case.

That's normal. It does that instantaneously when there very low load, AMD engineers are not dummies.

Don't touch vCore on Zen CPUs, especially Zen 3, it has curve optimizer setting, use that instead.

What specific models of PSU and GPU ? 750W is enough for RTX3080, RTX3090/3090 Ti would need 850/1kW respectively. Add another 100W if it's one of those unhinged Intel CPUs. Most PSUs work at these wattages with the exception of Seasonic Prime based units (so Corsair AX, ASUS THOR, Phanteks Revolt X and Antec Signature too), some (or most) Andyson designs such as EVGA GA and some High Power designs like Thermaltake Grand RGB Gold.

That's true for Seasonic Prime, but Focus seems to be fine. But Corsair RM/RMx or HX are still better than anything Seasonic so far, EVGA G6 (Seasonic-made) is pretty close tho.

Considering that efficiency has nothing to do with the actual quality of the PSU and Seasonic Focus is rather budget series, 65$ doesn't sound like a good price for a used one at all, i'm not sure if Seasonic warranty is transferrable or not tho, if it is then it might be fine. About a new PSU for the same price, there are sometimes some deals bringing the price of comparable PSUs closer to that but not right now, although you could've added just 20$ more for something like Corsair RM-x instead, a better PSU anyway. PS: God, i hate Comic Sans, this is not 1st April's joke, LMG, i'm suing you for emotional damages.

@AnonymousGuyConsidering that you don't have the new GPUs that would require those new connectors so you don't need a PSU right now, i suggest waiting maybe half a year for Corsair HX refresh, there's going to be 1.5kW model, similar platform to the aforementioned bq DPP12 but maybe it would end up cheaper, and you wouldn't need to swap the cables aside for adding the new GPU cables when needed.