Sam spontaneously hard-resetting :( [SOLVED]

Recently my Sam440 mini-itx has started spontaneously hard-resetting. It's OK when first used, but after being on for a few hours it starts resetting, and then happens very often until I leave it off for a while.

My first thought is that this could be a temperature issue, and my Sam's tiny case has no (active) fans. Does this seem reasonable? Any other possibilities?

Are there any utilities for measuring temperature under OS4? Or can I tell from Uboot? (Going to look now, but thought I'd ask the question while I was posting this.)

One thought I had is that maybe my small DC-DC PSU is having trouble at high temperatures, and might be on the way out. Anyone ever experience that before with a (non-AC) PSU?

@ChrisH

Never had any problems with this before. Only yhing that comes to mind is that the psu is not feeling well. Have you got another psu you can try???

sorry to hear your Sam is feeling sick Chris. In my experience, this type of problem is almost always related to a bad PSU. You can also try running the Sam without the case on and with a fan running on it to see if its a cooling problem.
Either way I would definitely always run a small fan in the case...more heat = more problems...this always hold true when electronics are involved

@Antique Quote:
Not without moving the mobo to a different case... which I may end-up trying. The PSU is custom for the small case I am using.

BTW, worth mentioning that it wasn't *that* long ago I installed a backplate in my case. Before then I had a whacking great hole at the back, which obviously would have been great for ventillation. At the moment I am seeing if ventillating it fairly well helps (early test was not hopeful).

@ChrisH

Just open the case,disconnect the psu. Screw the other psu from the other machine and put it next to the sam case and plug it in. THat's what i did when my psu stopped working. So you don't have to dissasemble verything just to check if it's the psu's fault.

@ChrisH

I'll add my vote for the power supply. I've seen the PSU as the cause of this many times before.

@ChrisH

I dont know how much help this is, but I normally get these symptoms on my PC when overclocking.

So I would suggest :

1) RESET Uboot to default, incase voltage to cpu/speed of cpu/ memory settings have been changed.

2) motherboard/circuits are touching something or a circuit leg touching another circuit.

3) Memory not sitting correctly or memory malfunction.

4) could be CPU not sitting correctly or cpu malfunction/overheat.

5) powersupply malfunction or too low watts (did you add/change the system last few days before problem).

6) Graphics card not sitting / malfunction

First test motherboard only, then add hardware step by step until you reproduce symtoms.

@Chris

i have sam440ep mini-itx like you and i never had that kind of problems and i leave the sam switched on for hours so i don't think it's a temperature issue.. I guess it could be a PowerSupply problem or your UPS.. check them..

@chrisH

Here's yet another vote for the PSU. You can connect any ATX-style PSU, it doesn't have to be dc-dc for the purposes of a test.

@ChrisH

In the PC world where my job is, this kind of problems have more to do
with memory, psu and temperture, in this line of order, and it's too bad
that in sam we don't have the option to try another memory...
As for the backplate, if you remove the board to put it in place,
the reassemble may not done well and the problem will gone if you do it from scratch.

I have SAM440ep and use only passive cooling - this is why I resigned to install backplate. However I have a suspicion that after couple of hours the system becomes more unstable than usual. Never experienced self reset in such situation - only GreamRipper or crash.

Therefore I'd vote for PSU or temperature issue.

@all
Further test showed that the problem did NOT appear if the top of the case was left off, even after many hours. So I concluded it is definitely a temperature issue (although it might still be a slightly faulty component triggered by high temp, but proving that would be hard).

My case came with two fans, which I have now activated thanks to a 3-pin power cable adaptor bought from Maplin. Is quite noisy (compared to how it used to be, although at least i can tell when it is on now!), but no problems yet.

I will see how it goes, and if no problem after many hours, then I will try disabling one of the fans for a quieter experience.


P.S. Alex_C mentioned system instability/crash after some hours of use. I have actually noticed that in some cases recently, but I don't recall it being a problem in the past. It had not occured to me this might be temperature related, so fingers crossed I also get a more stable system again!

@ChrisH

I like to run ordinary 12 volt fans at 5 volts. They run at about half the speed but make about a quarter of the noise and last for years. You could try it, it sounds as though you only just need a fan, running it at half speed may be all you need.

@Chris

I suggest you to contact Acube and ask them about some program to download in order to test your sam board, this to avoid mainboard problem. In this way you can check other components like PSU

@nubechecorre

if it's exist a program like this, it's place must be at osdepot too!
we may all need it at the future...

i don't know but maybe there is some tool under pc windows that can be used to check the board linked using the serial port.. well it' s only a guess i don't know..

Hi @ChrisH
#13 [b]...So I concluded it is definitely a temperature issue (although it might still be a slightly faulty component triggered by high temp, but proving that would be hard).[]

FWIW, from this A1-XE-G4, My UBoot won't boot at below 73'F without at least three minutes warmup.
I have a CoolerMaster case & gauges and calibrated temp probe in the CPU base.
http://www.flickr.com/photos/11367727@N07/2716912145/
As for too hot limit, 45'C is my limit cutout based on Quake2 load. Always choked and sputtered playing Quake2 because on the puny cooling system. Added a Zelman fan and ended that. I haven't foggiest what's required for SAM. You might want to use a micro fan; I would.

@tonyw

yes excellent advice Tony! I have two 12v slim cpu fans mounted in my stock 1200 case operating at 5v and a barely hear them...(keeps Blizzard card and Indivision AGA nice & cool)
it really makes me laugh when people say 'you don't need extra cooling'...honestly it's like saying 'you don't need extra cash'

In case anyone wondered, my two noisy fans do seem to have fixed my hard-reset/instability problem (touch wood).

@328gts
Good idea. Or I could put a resistor in series with the fan (will give the same effect from an electrical point of view, except I can choose any voltage).

I'll also try just having one fan running instead of two.