Computer power up and then off?

[craig]

Hi, just a quick question. When using my PC recently it suddenly shut down? When I tried to restart it after pressing the power button on it ran for about 3 -/4 seconds and then shut down!! After pressing the power button on again it started up the HDD light on front panel lit up and power light lit up but no screen activity? There is power to the monitor and CPU fan is on also power supply fan on. H/D/D is running but PC won’t even boot up. I think it could be Motherboard? Anyone have an idea?

Many thanks for any help or suggestions

Craigsb

[mjc]

Break it down to a bare bones boot...remove everything from the motherboard, including the RAM and try booting. It should beep at you. If it does, add things back one at a time...starting with the RAM, then video card (if you have onboard video, ignore that). If nothing happens, try a different power supply. If, after swapping power supplies, nothing happens, search the board for bulging or leaking capacitors (if you have good access to the board you can do this as step one).

[craig]

Hi, Many thanks for that MJC, will try what you suggest and i will reply back tommorow with a more detailed report of what i did and any results....

Thanks again

Craigsb

[Heartborne]

barebones boot is a good test. Overheating and a bad power supply are other possiblities, so please keep us posted.

[craig]

Hi MJC, Heartborne and all,

Just to let you know about my update as promised.

I carried out the process as guided by MJC, Heartborne and others, and broke system down till there was nothing left connected to motherboard except for the power supply connectors coming from power supply to motherboard. I then started the system up and did get the POST check ok. However I then put components back onto motherboard one buy one and rebooted to check for POST after each component fitted. Everything at this point still ok, then when I connected the floppy cable back to motherboard, it went back to the same state as it was when I first encountered the problem. I remember now that the floppy power light was on continuously before starting strip down but didn’t think this would stop system booting up. Could it?

I then changed the power supply and this made no difference even though the new power supply was a 400 watt version, as the original was a 350.watt so I reverted back to the original 350.watt power supply. I repeated all procedure again and by this time was a bit fed up to say the least, only because I still had not got to the bottom of it. The order I reconnected components each time was as follows: Ram, then video card, Hdd, and than CD drive.

Repeated the process again as before and this time didn’t connect floppy, and this was ok. However, when I connected the CD drive it went back to the same state again. Finally, I repeated procedure again; rebooting each time and it did boot up and give POST each time. I have checked the power supply and temperature that the processor is running at as suggested by Heartborne and all still seems ok.

An extra bit of info is that when I removed all components originally there was an eternal sound card, modem and 100bit network card, I have not yet fitted any of these back into the system. I am using the system to compile this reply and have also been on net etc and as yet no problems. The only thing left for me to do would be to try a new floppy with new cable and also fit the sound card. Before I forget, the Motherboard has on board sound. I am a professional musician and as such use Cubase VST software for recording Piano and Hammond organ and other instruments, so that’s why I have an E-Mu, E-DSP sound card. I will report again onto forum when I have completed all installations and tried system etc. Please let me know if there is anything I am not looking at

Regards again

Craig

[mjc]

Is it currently running with or without the CD?

[craig]

HI again,

MJC, Its running at the moment with the CD device and its related cable connected to the motherboard. I don't have a spare new floppy disk to connect today and as I don't use floppies much. I have set the bios to boot from the HDD but it still comes up with the following message, “Floppy disk fail (40) Press F1 to continue, DEL to enter setup”. So I press F1 and then the following message appears Press (Ctrl + S) or F4 to enter RAID utility. I can understand the floppy error message as it’s not got one connected but what is the RAID telling me. The only thing I remember is that when I first had the problem I thought it was the HDD no being recognized so it changed the BIOS to load default settings. Was this a mistake?

[mjc]

No, reloading the defaults is often a common step in troubleshooting.

You can go back into the BIOS and disable the RAID if you aren't using it.