Help...computer not booting after power failure.

[Strenge]

Greetings everyone. Anandtech lurker, I've enjoyed the site for a long time, and now I'm hoping the community can help me find this problem.

I'm not terribly good with hardware (web and database scripter/programmer by trade), so please bear with me 🙂

As the subject says...Yesterday I had left the machine on, went out for a while and when I came back it was obvious we'd had at least a brief outage. (Of course, my apc ups is not working correctly and I haven't yet bought another one 😛)

When I powered up, I hear a single, normal beep; then about 6 seconds later I hear a second single, short beep. The screen displays the 'Main Processor' message, followed by 'Press DEL to enter SETUP' at the bottom, followed by the mobo info just under that. Then, nothing....it hangs at that point.

The keyboard never lights up, so I can't press DEL. It is not a usb keyboard. I tried another keyboard from a different machine, no go.


System info:
case: Antec SX630II (smartpower 300W psu)
mobo: MSI K7N2-L
cpu: Athlon 2400
mem: 2 sticks 512M 2700
bios: Says Phoenix-AwardBIOS v6 at top of screen

What I tried:
Tried booting with each of the mem sticks out. Tried an XP cd, doesn't get that far.
Tried booting with the 'clear CMOS' jumper set, got a blank screen, so moved the jumper back to 'save settings'.
Have not tried disconnecting the HD.

Things noticed that may be odd:
Besides the keyboard not lighting/working, the floppy never lights. The cd-rom blinks in rapid succession *twice* (two sets of multiple blinks seperated by a couple seconds). However, for all I know this is normal and I never noticed it.

In short, it doesn't get very far...my (probably faulty) reasoning brings me to the conclusion that the mobo may be bad:
*the psu obviously powers up *some* things at least, like the cd-rom, vid card, and all case, cpu and psu fans;
*HDs seem to be on (from sound and heat);

Any help you can provide would be greatly appreciated, at least in possibly targeting the problem part(s). Thanks!

*Edit, typo

 

[compso]

I would pick up a PSU tester or use a digital multimeter to test the rails of the PSU.

If that doesn't work you could try extracting your PC hardware and setting it up in a
HSPC Tech Station

I would also definately replace your UPS first thing, I like Belkin UPS.

 

[Strenge]

Tested the three rails (12, 5 and 3.3). They all were very close.

So, the psu looks ok? This is all hardware a few years old, it may not be worth taking it to any sort of repair place (unless I can get the guys at work to take a peek 🙂).

The more I can find out on my own the better. Any next step I can try?

Thanks so much for the help, it's good to be able to take *some* sort of troubleshooting steps!

 

[compso]

Until I get a second to think can you replace your UPS ASAP so we can atleast have clean electricity?

 

[Strenge]

I stole a ups from another machine, it's now hooked up.

As an experiment, I tried disconnecting the dvd drive, both hard drives and the floppy drive, but there was no difference.

Once again, thanks for the reply.

 

[montag451]

If something like this happens, really, the only thing you can do is unplug everything from psu and from mobo.
Now,
Plug only the following into the mobo:
cpu+fan
psu (inc 4 pin for cpu)
mobo speaker (to hear those little beeps)

The only thing that should be plugged into the psu, is the mobo.

Switch on using a screwdriver to trip the power sw on the mobo - any beeps?
If not - then it is a problem with mobo/cpu/fan/power issue (~including power button)
If yes, how many beeps?

 

[compso]

Ya, get a post beep code or video code. Try replacing the 3V CR2032 CMOS battery with another, they are cheap and available at Safeway, Walgreens, RiteAid, etc. Let us know.

 

[Strenge]

Update: Well, things are working again (!)

I brought it into work (slow today), and it and a tech noticed a power connector was not plugged in. It was a small one that I believe goes to the front and back case fans only. I think I remember disconnecting it, since I didn't think I needed the front fan if I wasn't overclocking...anyway, he plugged it in and the machine booted normally. Coincidence or not, I don't know. Perhaps moving the darn thing bumped something back into place (although when it stopped booting it hadn't been moved). He looked for any resistors that looked burned out but didn't see anything.

In any case, color me confused but relieved. Thanks for the help, it's been educational for me in learning how to troubleshoot issues like this.