PSU requirement for J3455-ITX setup

Runenaldo · Apr 9, 2017, 6:35 PM

So I got my system up and running with pfsense, but have only tested it with 30/30 mbit as I'm on easter holiday at my parents. 100/100mbit tests will begin next week ;D

Running pfsense seems to cause no stability issues, but haven't maxed the system out yet, so wanted to test it running prime95 in windows 10, but then i started getting red pixels, flickering screen starting aprox 2-3 minutes after booting into windows for the first time. and on top of that being unable to boot into windows after installing vga and or chipset drivers..
I've searched the internet in hopes of finding "the" solution or others with similar problems, but the best guess I can find is a bigger psu.

I have tried giving the gpu 512mb shared ram, with no difference.

So as I dont want to have issues next week, what amount of watts should a potentonal new pico psu have?
Or could there be something else wrong?

MB ASRock J3455-ITX 90-MXB3W0-A0UAYZ
RAM 2x4 GB DDR3L HyperX 1866 MHz
SSD Liteon 256bg
PSU 60W came with the case

Power consumption: (at the wall, acording to a cheap powermeter)
pfsense 11-15w
win 10 20-22w

pfBasic · Apr 9, 2017, 8:41 PM

I don't think PSU is your issue. I don't think that those components are even capable of drawing 60W.

The picoPSU wouldn't solve your problems over the PSU you already have (unless it's defective, which I doubt).

My guess is that your problems will go away when you install pfSense and stop running prime95 on it.

Runenaldo · Apr 9, 2017, 9:14 PM

So i have found your recommendation for the J3355 http://www.mini-box.com/picoPSU-80-60W-power-kit
Is this valid also for J3455?
My case came with a 60W "pico" PSU , could be a cheap no good one, but shouldn't it be the same as the one in the link, since it only comes with a 60W adapter? Also why put an 80W devise together with a 60W adaptor?

@pfBasic:

I don't think PSU is your issue. I don't think that those components are even capable of drawing 60W.

The picoPSU wouldn't solve your problems over the PSU you already have (unless it's defective, which I doubt).

My guess is that your problems will go away when you install pfSense and stop running prime95 on it.

Yeah, couldn't get my power readings to coralate with 60W being to little, even though that seems to be the consensus for this type of behaviour.

Even though the system may run perfectly fine on pfsense, it bugs me that there clearly is something wrong with the board, since it should be able to run win 10 without any issues.

I never got to run prime95.. which is even more annoying.

pfBasic · Apr 9, 2017, 9:44 PM

You are right that it shouldn't display any issues regardless of OS.

If you have another PSU available try using it to see if it solves the issue. If so then your PSU is faulty and you should get it replaced.

Other than that you could run tests on your RAM maybe?

Probably either a faulty PSU or a faulty board.

Pairing the picoPSU 80 with a 60W AC/DC adapter is actually a better setup for a low power appliance.

The picoPSU itself is DC to DC, it's extremely efficient but it isn't really the component doing the heavy lifting.
The AC/DC adapter is where the efficiency loss happens. PSU's are rated for x% efficiency at "normal" load which will be some value relatively close to its design power. A top tier 1000W gaming PSU with the best 80+ ratings would have pretty crappy efficiency when only pulling 10W, it just isn't what it's designed to be good at. So ideally you would find out what the maximum power your system is capable of pulling form the wall in a worst case scenario, and buy an adapter rated for just a little more than that. But in your case that's probably like 30W and I don't even know if you could hit that.
Anyways, the 80W AC/DC adapter won't give you any benefit in this application and would actually hurt your efficiency (although by a pretty negligible factor in terms of $). But the fact that the AC/DC adapters are generally cheaper for lower power units in the first place means pairing it with something rated for lower power consumption is an all around win!

Runenaldo · Apr 10, 2017, 10:13 AM

Once again "KISS" is the best option..

I tried many things, but in the end it was a faulty HDMI cable that was the culprit.. ::)

Running stress tests now with prime95 and after 10 min it seems to be stable at 70 degrees at a room temperature of 20 degrees, its drawing 18-20W