[Newbie] Mini-ITX Mobo in 2023

[Etorix]

I'm not sure what you mean, if i were to determine that it's better to count the fans as higher wattage for safety reasons... wouldn't i have to recalculate a new safety margin given the new numbers?

Yes, but the "safety margin" is something fuzzy, and since you can't buy a PSU at any arbitrary power (I've never seen a "587 W PSU", for instance) you'll end up looking at the same products anyway, at the same predefined power levels (450 W, 500 W, 650 W). So getting "the right number" becomes a purely academic exercise and you should now move on to practice: Get a good quality PSU from a reputable supplier (Seasonic, Corsair… in SFX size I would also look at Fractal Design), with the highest reasonable level of 80 Plus rating. "Reasonable" meaning that, while higher is better, it might be that the extra cost of a Platinum PSU over a "mere" Gold PSU will NOT even be recovered through lower power draw over 5-10 years of NAS use, and that, if cost matters, it might well be acceptable not to go for the highest available rating.

 

[jgreco]

The lower, the better.

Not always. Don't tempt people to significantly undershoot. If you calculate (by my methods) that you need 473 watts, you are still pretty well in the safety margin if you go with a 450W, but you're really better off with the 500W. There's been a constant stream of people who argue that they want to go much lower, much closer to observed idle, but the point is that you can damage your system and expensive drives if you don't supply the watts your system actually requires. Lower is not better. Lower within a stone's throw of the calculated number is probably okay though.

 

[Davvo]

Not always. Don't tempt people to significantly undershoot. If you calculate (by my methods) that you need 473 watts, you are still pretty well in the safety margin if you go with a 450W, but you're really better off with the 500W. There's been a constant stream of people who argue that they want to go much lower, much closer to observed idle, but the point is that you can damage your system and expensive drives if you don't supply the watts your system actually requires. Lower is not better. Lower within a stone's throw of the calculated number is probably okay though.

Yup, not always: after all the calculations and the safety margin, in the range from 450 to 650: adding 60 W to the 285 W value we get 345 * 1.25 = 431 W which means a 450W PSU; I don't know why your calcualtions came up with 473W, am I missing something?
It's also a matter of what is on the market. I'm not seeing availability in anything lower than 600W (from reputable brands, SFX).

I'm not, in any way, suggesting an undershoot (let alone a significant one).

 

[Ericloewe]

The market has broadly moved to higher power ratings as efficiency improves, allowing for bigger numbers in the same size of chassis; and as component power consumption is again trending upward, after a decade of roughly-constant CPU TDPs and a veritable roller-coaster of GPU TDPs from high (and/or multiple GPUs) in the early 2010s to lower mid-decade with single GPUs to "we needed to design a new connector and it still can't handle the full power consumption" right about now.

450W was a common power rating a few years ago, but it seems to be falling out of favor.

 

[Davvo]

Yup, it appears that 650 is the new 450.

 

[neetbuck]

(450 W, 500 W, 650 W)

I was wondering if by recalculating for a higher power draw for the fans would shift the range upwards, which is incorrect, but I'm also a bit skeptical about the low numbers on the SSD boot-drive... is there also, like with fans, the possibility that it will draw more power in a freak accident or unexpected scenario?

Don't tempt people to significantly undershoot

I don't think he's telling me to undershoot significantly. Our conversation has gone something like this:

- I initially made a power consumption calculation/chart based entirely on your guide, and asked if the results were overkill [374W*1.25=467.5]

- Davvo replied with a revision where he went in and found in the specs for some of the components what the brands said the max. power consumption was & added 25% for derating [285W*1.25=356.25W]

- Then I've continued to ask questions because I wanted to understand better, because I feel cautious about not sticking to your guide religiously, & because i don't believe what a brand says about their specs (since I don't believe they take into account 'anomalous' situations).

In other words I've been ready to almost just get a 750W PSU and Davvo has been talking me down from going over the spectrum he calculated and trying to keep me on the lower end of it - which I appreciate since it seems like going over can cause problems beyond just inefficiency (as Etorix pointed out to me).

I don't know why your calcualtions came up with 473W, am I missing something?

I think he was just giving an example of a number above 450W and below 500W and hasn't really looked at our calculations (though I could be wrong)

I'm not seeing availability in anything lower than 600W (from reputable brands, SFX)

I can get 450W SFX Corsair model that is 80 PLUS Platinum, it's from a supplier I don't like though (horrible reviews lumped with some good ones). That said I'm still a bit cautious about going for 450W instead of 500W-600W (well, 600W since I can't find any 500W models)

 

[Davvo]

That said I'm still a bit cautious about going for 450W instead of 500W-600W (well, 600W since I can't find any 500W models)

If you feel more at ease with 600W, go with that. Your system, your call.

 

[Etorix]

In other words I've been ready to almost just get a 750W PSU and Davvo has been talking me down from going over the spectrum he calculated and trying to keep me on the lower end of it - which I appreciate since it seems like going over can cause problems beyond just inefficiency (as Etorix pointed out to me).

Not "problems" as in "risk for the server or its data" but overspending for no good result and even minor adverse consequences.

But at this point you're on the right track. Whether you go for 450 W, because it fits, or 600 W, because the supplier is known to be reliable, your call should be "the right" call.

 

[neetbuck]

If you feel more at ease with 600W, go with that. Your system, your call.

fair enough, it's not like there are many options:

- The seasonic gold sfx line (sgx) seems to all be sfx-L... but I haven't found anyone using an sfx-L psu in a Jonsbo N2 build... so I'm not about to run that risk of testing it out if it will fit or not.

- The 450W SFX Corsair... I've decided to avoid the shop that sells it after rereading the trustpilot reviews.

- The fractal PSUs someone mentioned earlier are also sfx-L.

I'm basically stuck looking at the seasonic SPX 650 and the Corsair SF600 platinum.

- The FOCUS SPX 650 I'm sacred of, because I've seen bad reviews of the SPX 750 - idk if anyone has any thoughts on this.

- The Corsaire SF600 seems like the best choice, although I have to say, at least the exterior build quality looks cheaper on it than on the Seasonic and it has one less socket for SATA and PCIe. Additionally it would arrive around the second half of august, which has me tearfully eyeing the SF750 which would cost me 10 euros more and would arrive in two days.

I hate to keep poking at the same thing, but I don't 100% understand the negative impact getting the sf750 would have - specially given that 10 euro difference in price - can anyone explain that to me in a clearcut way? or would it not be that bad?

even minor adverse consequences

minor? I maybe misunderstood your earlier message, but I thought you said that it could result in elevating temperatures inside the NAS? I don't think that would be exactly minor, unless it's barely perceivable.

 

[Ericloewe]

The FOCUS SPX 650 I'm sacred of, because I've seen bad reviews of the SPX 750

Whose reviews?

 

[Davvo]

I hate to keep poking at the same thing, but I don't 100% understand the negative impact getting the sf750 would have - specially given that 10 euro difference in price - can anyone explain that to me in a clearcut way? or would it not be that bad?

Most of the time your system will not draw enough power to let the 750W PSU work in an efficenct way.

 

[neetbuck]

Whose reviews?

I guess it's the one review people keep referring to.

even if it's one though... I haven't seen anyone refuting it or touting how amazing the focus spx 750W spu actually is.

Most of the time your system will not draw enough power to let the 750W PSU work in an efficenct way.

Meaning... it will drive my energy cost up? or what else? And if so... but a significant amount? Energy cost for me is pretty low.

 

[Davvo]

Meaning... it will drive my energy cost up? or what else? And if so... but a significant amount? Energy cost for me is pretty low.

Under 20% of load the 80+ certification doesn't apply (except for titanium?), meaning you would likely have a significant reduction of the PSU efficency. Can't quantify it, but it means a sure energy cost and heat increase.

 

[Ericloewe]

uess it's the one review people keep referring to.

even if it's one though... I haven't seen anyone refuting it or touting how amazing the focus spx 750W spu actually is.

The author is credible and the issues make sense. The more minor gripes make it sound like an overly-ambitious product at 750 W, though OTP is the only serious issue.
In practical terms, I don't expect it to be a problem under realistic conditions, which is only small comfort.

Personally, I think I'd steer clear of the 750 W but might still buy the 650 W unit.

 

[neetbuck]

Can't quantify it, but it means a sure energy cost and heat increase.

hmmm fair enough. I'll skip the 750w models.

but might still buy the 650 W unit

over the SF600 Corsair? (The only other model I haven't discarded)

Also, any thoughts on opening up myself considering Gold rated options too? I see some discussion between people saying there's barely any difference, just a few percentage points, meanwhile other people insist there's a worthy difference in build and component quality - and even the cables that come with.

 

[Davvo]

Also, any thoughts on opening up myself considering Gold rated options too? I see some discussion between people saying there's barely any difference, just a few percentage points, meanwhile other people insist there's a worthy difference in build and component quality - and even the cables that come with.

Also compare price differences and warranty lenghts, as well as availability and ease of acquisition of extra cables.
If your energy cost is low, you might save a bit of money going for a gold rated instead of a platinum one... but I don't think it's significant. At the same size (ex 450w, 650w, ecc) higher-rank certifications have better components/designs than lower rated ones in order to improve the efficency.

 

[Ericloewe]

over the SF600 Corsair? (The only other model I haven't discarded)

In a vacuum, not really. I have bought into Seasonic Type 2 cables, so I try to stay with Seasonic as much as possible, which changes the calculus a bit.

 

[neetbuck]

you might save a bit of money going for a gold rated instead of a platinum one

I was more considering it because of higher availability and because there are 500W models. That said I'd rather get something with as good a build as possible.

In a vacuum, not really.

Earlier you said you'd steer clear of the 750W given the poor review, but you'd give the 650W a chance... why so? they're from the same line, wouldn't it be safe to assume they have similar issues?

 

[Davvo]

they're from the same line, wouldn't it be safe to assume they have similar issues?

Not necessarely, designs might differ a lot from each model... that's why PSU shopping is so damn hard. See and compare:

Seasonic FOCUS PX-650 Platinum Review - KitGuru

Today we look at one of the latest power supplies from Seasonic. The FOCUS PX 650 is part of an inte

www.kitguru.net

Seasonic Focus SGX-650 Power Supply review

The Seasonic Focus SGX-650 is a small form factor (SFX-L) power supply, but it’s still possible to install it in ATX systems. It has 80 plus Gold certification, which means that it&rsquo... Final Words & Conclusion

www.guru3d.com

Seasonic SSR-650PX PSU Review: High Performance Without Breaking The Bank

The Seasonic Focus Plus Platinum 650W is a high-performance PSU suitable for systems where efficiency and low noise output matter the most.

www.tomshardware.com

Though none of those tested the same way your linked review did, so it might have eluded them.

 

[Ericloewe]

I was more considering it because of higher availability and because there are 500W models. That said I'd rather get something with as good a build as possible.


Earlier you said you'd steer clear of the 750W given the poor review, but you'd give the 650W a chance... why so? they're from the same line, wouldn't it be safe to assume they have similar issues?

They're the exact same design with minor parts changes, I'm sure. In practical terms, that means less waste heat in the same package, so less risk of overheating.