PC Goes Off and Re-starts

[Debbie]

I have a PC with a new Asrock 478 socket MOBO. Randomly, when I turn it on, before posting, it goes off for a couple of seconds and on again. Then it keeps going steady as a rock. I have checked the RAM and found it OK.

[High_Jumbllama]

Sounds like a power supply or mother board issue. Check all connections assuming you have not already and then try swapping the power supply and flashing the motherboard.

Any caps bulging?

[Debbie]

PSU changed , caps OK, all connectors checked. I think I'll wait and see what happens next. As things stand, I only have to wait a couple of seconds more before It'll get going.

[VJ]

Is all the memory of the same manufacturer and the same size?

[lowlifecat]

experiment:

turn off the PC via the PSU (there should be a primary on/off switch on it). let it sit in Off while still plugged in for around 15 seconds.

remove power cable then plug back in. turn on PC.

does it still "hiccup" when starting?

optional: remove any USB connections that have a powered hub on the end (i.e: if you have a USB hub connected that is powered with a DC charger). unplug VGA/DVI/HDMI cable as well. then try above experiment.

[VJ]

lowlifecat: are you thinking about grounding issues?

[lowlifecat]

Yup. Grounding/static issues is the first thing I check for with any type of boot issues.

[Debbie]

I think I found out what's happening (I hope). Asrock have what is called "boot failure guard" in the BIOS setup. This is meant to protect the CPU if overclocking. I am using a CPU with the maximum specs. and this perhaps is in some way having to do with this behaviour. I have disabled this feature and since have had normal booting. I'll have to wait and see.

lowlifecat, I'll do the test if the symptom comes back. Thanks.

[VJ]

My weirded boot issue was a computer that refused to boot, but some led on the mainboard were lit (fans were spinning) when I powered it on. I couldn't figure it out for the life of me, so I decided to completely take it a apart. While fiddling with the front panel, the reset button suddenly went POINGGG and shot true the room.
Yep, the internal button was stuck, but the one on the front panel did not reflect this...

[Debbie]

I'm back to square one. I did what you sugested, lowlifecat. However I can't be sure because it is a random behaviour. I could power up a dozen times and have no problem but eventualy it will do it.

[degrub]

the way we used to find random electronic connection failures was to take a can of freon and spray the connection or chip briefly - the drop in temperature would expose any bad solder joints or chip faults. Don't know if you can find an hcfc in a can anymore, but check out a local electronics supplier.

[Debbie]

I just have to try and find a patttern. All I know is that it will boot without problems on restart. It does it mostly when starting up from cold. As I said further up, it only restarts once, after a couple of seconds and after that it goes on without a hitch.

[VJ]

When did it start? Or is is a brand new system (or new mainboard)?

My guess is still on memory configuration, how are the memory banks populated?
Or power: could it be that some devices are drawing too much power on startup?

It could also be a hardware conflict, nothing in the FAQ of the manufacturer? (e.g. my Supermicro is incompatible with the Parhelia, in that it sometimes refuses a warm restart. This is on the Supermicro FAQ, but they claim it is solved with later bios versions, but it is still occuring on my system).

Jörg

[Lambo-Fan]

Maybe your PC is suffering of the so called "cold boot bug". Some P45 chipset based mainboards show this if an invalid RAM speed has been set up.

On the other hand I don't think that you set up wrong things in the BIOS.

Speaking about a possible grounding issue: Wouldn't the system in that case refuse to boot at all or wouldn't it be instable the whole time? I can't imagine that a grounding problem only would affect the boot process.

[Debbie]

As for RAM, I have a matched pair of Corsair DDR1 400 MHz. All the divices I have are: A PCI to SATA converter board. A fire wire board and a ATI All-In-Wonder Radeon 9800 video capture card. I have removed these cards and still the machine will randomly re-boot once. I will check the PSU next.