PC Fan Spins For One Second And Stops - No Bootup

[WeaponX 0]

I just want someone to confirm this before I go online and buy the part (which is probably going to be expensive).

 

Just took a look at my cousin's Acer (ASUS) Pundit computer. It's one of those small form factor machines. Well, I pushed the power button and the power lights up for one second and shuts off immediately. I popped the little critter open and watched the fan spin for one second and then stop. I have to unplug the cable and replug it back in, in order to push the power again to see if turn on for one second...nothing.

 

My first guess was power supply...then I used one of my power supply testers on that 20 pin (I think) power cable and the fan started to spin...no problem there This is my first time using a power supply tester, but I assume that means it's definitely NOT the power supply.

 

So right now, I'm guessing is has to be the motherboard right? Like I said, I want to make sure this is the correct piece to get since it will probably be expensive since this machine is not that old (about a year only). Not sure how I can test out a motherboard to be sure it's not faulty (like using power supply tester for power supply testing), so if anyone has ideas on how to do this, I'm all ears If it helps, the ethernet port is lighted up when the power cord is plugged in...but I don't think that means anything. Board probably still bad?

 

Thanks.

[grnjd 0]

Maybe it has something to do with your bios or there is something wrong with your drivers. If all else fails just do system restore, if that doesn't do, format your computer and reinstall windows. But that'll take a lot of time...

[HellFire121 0]

system restore, formatting or reinstalling windows might be a bit hard since the computer is only on for 1 second

[James_K 0]

I think your best guess is to start looking at some of the other hardware components it will probebly something major since usually if there is a hardware malfunction the POST will tell you MB internal speaking to start annoyingly beep my guess is that it could be a faultly processor usually computer tend to shutdown by them sleves because it the processor is over heating although I'm sure thats not that case because your processor must be pretty hightly clocked to be overheating in one second but you might want to check like trying a different one maybe the processor is sending false reading or something like that also keep in mind you FSB could be cracked I shipped my computer ounce and fedex cracked my FSB and it would as a BSD so yah check all your hardware try replacing as much as you can with spare units but make sure they are compatible before you try. Good Luck!

[Logan Deathbringer 0]

ok here is what I would do if the computer was sitting on my bench at work.1) pull out a power supply and see if I can get the thing to boot with a backup unit.2) if that didn't work I would then replace the Lithium Ion watch battery and see if the system will now boot, if this little bios battery is dead most computers will not boot.3) then if all else fails I will then start thinking the motherboard is dead and then order/replace it.hope this helps and if you need more help post again. Also let us know whats going on with a post or 2.

[WeaponX 0]

Great suggestion Logan I actually didn't think about the CMOS battery but definitely will give that a try. Stupid too...I was staring at the board that day and looked straight at the battery...mind is not working like it used to I will post updates on this situation. Hoping it's the battery now Thanks.

[Logan Deathbringer 0]

I personally think its funny that there still hasn't been any change in the way motherboards operate. By that I mean that they haven't set them up to run the bios power off of the power supply unless power is lost then switch to the battery. I find it plain stupid, that with the level of tech we have these days we still don't power the bios off of a power supply so that if the battery dies we can still boot and get a warning on the screen rather then a totally dead system.Just my opinion is all, you'd be surprised how many computers I have come to me that I all I have to do is replace the bios battery and I charge 80 to 120 USD to replace a 3 USD battery ....

[wutske 0]

In fact, I am pretty shure it has something to do with the PSU.PSU testers are fine, but not perfect, so don't just trust them blindely, because there are 2 causes that make a PSU shutdown:Overload (if not connected to the mobo then it will boot because the CPU and VGA won't load the psu anymore)ShortageTry disconnecting things like the hdd, cd and floppy and try again. Maybe removing an expansion card or even the vga card could help.Other thing could be the overheat protection. Check if the cpu heatsink is still descently on the cpu. But I doubt that that would be the problem, because even a full loaded P4 can run heatsinkless for a few seconds.Or is it a mobile cpu w/o a heatspreader ??? Because then it might work that fast.Last thing I just think about could be a faulty cpu or cpu settings. Maybe that a CMOS reset helps ?

[qwijibow 0]

We have had quite a-lot of wild guesses, some from people blaming the OS before the disk has even had time to spin up, lol....anyways, after testing the PSU, i would agree that its probably a BIOS issue. My first computer suffered exact same symtoms (which diesnt necceserily prove that its the same problem)Unfortunatly for you... its usually easyer to replace the whole motherboard than it is to get a new bios chip, and then get that new bios chip flashed with the correct bios firmware.but with new motherboards as cheap as £15, who cares.

[WeaponX 0]

I still didn't get a chance to go back yet, but it's working again...for the time being. Could it still be the PSU in that case? I'm taking a battery with me next time just to be sure.

I recall seeing the heatsink intact, but will make sure it's seated properly when I go back. I will test out the PSU by unplugging some parts to see if it still has that one second startup/shutdown...

Found the motherboard (barebones) here. Basically that's what they are using.

[Grafitti 0]

This one second boot happens to me when either my power suppy isn't working correctly, or when the bios thinks the processor or a component on the motherboard is too hot. What solved it for me was that the thermal compound was dried out and cracked. so once i replaced it it took care of most of those problems.

[iGuest 3]

I HAVE THE ANSWER!!!!!

PC Fan Spins For One Second And Stops - No Bootup

 

I found this thread when I had the same problem last night. Just moved my computer to a new tower case.

(Monolith)

Same exact problem. Tried a new bios battery. Nothing.

The same thing was happening on 2 good power supplies.

 

Led/fans kick on for a split second, then total shutoff.

 

Took my motherboard out of the case because it was working that morning in my stock HP tower. Held it in the air by the heatsink and plugged the 24 pin power and 4 pin power into it and nothing else.

 

Vuala! cpu fan starts and stays on. After going through the process of elimination I realized THE MOTHERBOARD WAS SHORTING ON THE METAL CASE.

If you haven't resolved it yet, try putting a non conductive foam or plastic between the case and your motherboard. I believe they sell them at electronics stores. Good luck!

 

-reply by ryan

[mikesoft 0]

ok this thread is like 1 year or maybe 2 years old :)anywaycareful, if you put foam between the motherboard and the metal case, the foam will most likely hold motherboard-generated heat, so you might get some errors/crashes due to overheating. If installed correctly, the motherboard should never have to touch the metal case, so you don't need to put anything between them.

[iGuest 3]

This is an asus mobo and this issue is common on most of their boards..The mobo overheat protection has a strange way of detecting if the heastsink is seated correctly on the cpu, everytime I've seen this just pull the heatsink/fan assembly off the cpu being careful that the cpu isn't stuck to the heatsink and then just put it back on. This has fixed the possibly same problem your expierencing.-reply by Philipg71

[iGuest 3]

I had the same problem I did what ryan suggested about holding by the fan and the thing booted up,, Glad I found this site.Thanks ryan you a Star mateMike-reply by michael