CPU How to use ATX PSUs on thin-ITX boards?

[cleveland]

I'm a huge fan of thin-ITX boards: lower overall volume, DC-input operation and some of them even have the ability to host a low power GPU!

With all of that in mind, one thing bugs me: there are several manuals stating that some of these boards can be powered by atx PSUs. To be pretty precise, they can be powered by the 4pin EPS connector. Beyond the fact that we can make a PSU run "always on" by hooking the 16th pin with any ground wires, I'm really interested in having a rig that can be "normally powered off", by the press of a single button.

The question goes here: is it possible to connect the PSU and front panel wires in some sort of circuit that, by pressing the power button, the system turns on/off (the PSU and then the mobo, in that specific order)?

If you guys need some pics to work with, here is the hardware I have to work with: GA-h110TN-M, paired with an Enhance ENP-7025B.

The red circle on the mobo's pic is where the manual states that the EPS plug goes in.

 

[DASBOOT]

I believe these are 12/19v boards, not true 19v boards. These boards can also be powered by 2 pins rather than four pins but it is not recommended for higher wattage CPUs. There are keyboard power-on boards out there controlled by a bios setting. (Atx, SFX, SFXL, power supplies do not supply 19 volts.)

 

[Goatee]

You don’t need a full atx psu, just a 12 or 19v supply (depending on your board). HDPLEX do a 80 or 200 or 400w ac/dc that can be used to supply the board. Depending on the model and version of the ac/dc you get they even come with the four pin connector.

Are you set on using a flex supply?

 

[DASBOOT]

HD Plex has suspended production of 200 watt PS's indefinitely due to required current ridiculous internal component costs most likely due to the Rona. The 200 is the ideal size as it is shorter than the 400. (400 would be needed if you were going to discrete graphics)

 

[REVOCCASES]

you could also have a look at one of those PSUs that are used in AIO PCs from HP, DELL, LENOVO, etc. then you do not have to worry about PSon because they are designed to work "like a brick" = always on.

they are available with 12VDC / 19VDC up to ~200W. If you have some airflow in your case they don't need active cooling plus they are cheap. About 20 to 40 bucks second hand, depending on the condition.

Some examples I used with Thin ITX before:

• HKF1301-3B (19V 130W)
• 792224-001 (12V 200W)

Edit: some of those 12V/19V AIO PSUs also share the FLEX form factor if that would be easier to integrate in your planned build.

 

[cleveland]

I believe these are 12/19v boards, not true 19v boards.

Absolutely right on the spot. Even the manual states that. Maybe the voltage is even wider, but I'm not testing it

Are you set on using a flex supply?

Yes. Mostly because the PSU is already at my desk, but also because I don't wanna mod the case I'll be using this time.

 

[cleveland]

you could also have a look at one of those PSUs that are used in AIO PCs from HP, DELL, LENOVO, etc.

Hey, that's great news, especially because they are about the same size as the Flex PSUs. If they don't cost a lot where I live, maybe I'll give it a try. Thanks for the tip!

Also, do you think it's safe to mod and use the Xbox's PSU to supply the 12v needed? I mean, the connectors need to be changed and everything, but the voltage is right, the size is about right and it's even easier to find one than a reputable flex-atx PSU out there... and that's not even mentioning the noise. Oh, Lord, the noise!

 

[REVOCCASES]

Also, do you think it's safe to mod and use the Xbox's PSU to

Sure, why not. That's also an good PSU. And as long as you have some airflow around it doesn't need an active cooling fan.

Just make sure to buy from a seller with good reputation. I've had a couple of those AIO PSUs which were offered as "brand new" and they were fake.

 

[Arboreal]

Thanks for posting about these PSUs @REVOCCASES. I have seen them in passing in the past, but paid any attention to them.

I've always avoided tinkering with PCs that have proprietary power setups and odd shaped boards, other than renovating any that came my way.
Had a quick look on UK ebay, and there's an HP 792224-001 for £40, which doesn't seem unreasonable. Would it be quieter than a Flex ATX PSU? I guess probably so as it;s not going to be heavily loaded.
I own a couple of thin ITX boards and haven't powered one via the 4 pin socket yet; something I need to address!
Bring on 12VO as soon as you like!

reputable flex-atx PSU out there... and that's not even mentioning the noise. Oh, Lord, the noise!

Absolutely, my 4.5L case from @CC Ricers was painful to use with an i6 4570 and GTX 1050 Ti on Flex. It's now running an i3 on a brick powered thin ITX with 2 big 3.5HDDs in there as a remote backup unit.

 

[REVOCCASES]

Thanks for posting about these PSUs @REVOCCASES. I have seen them in passing in the past, but paid any attention to them.

I've always avoided tinkering with PCs that have proprietary power setups and odd shaped boards, other than renovating any that came my way.
Had a quick look on UK ebay, and there's an HP 792224-001 for £40, which doesn't seem unreasonable. Would it be quieter than a Flex ATX PSU? I guess probably so as it;s not going to be heavily loaded.
I own a couple of thin ITX boards and haven't powered one via the 4 pin socket yet; something I need to address!
Bring on 12VO as soon as you like!



Absolutely, my 4.5L case from @CC Ricers was painful to use with an i6 4570 and GTX 1050 Ti on Flex. It's now running an i3 on a brick powered thin ITX with 2 big 3.5HDDs in there as a remote backup unit.

I'm using the 12V 200W HP in my 3L DIY eGPU for quite some time now. It doesn't have a fan so it's absolutely silent. If you are running it at constant high loads it wouldn't hurt to have some airflow around it, so I added two temp controlled Panasonic fans in my eGPU.

Note that there are different revisions of that PSU with different efficiency ratings. If you can, try to find the one with Platinum rating. This can even handle 250W peak for a short time.