This one is a well known sign to techs all over. They know to open it up and inspect for BAD CAPS.
Here's links in case you need to know more.
http://en.wikipedia.org/wiki/Capacitor_plague
http://www.badcaps.net/pages.php?vid=5
http://news.cnet.com/PCs-plagued-by-bad-capacitors/2100-1041_3-5942647.html
This has not subsided from what I can tell. But has spread to TVs and more.
It's a shame more details were not told such as age, if you tried a new CMOS battery, etc.
Bob
I have a DG43NB motherboard which has developed a weird start-up issue. When the computer is first powered up, All of the drive activity lights are lit, and the fans run at full speed. But no video, no beeps no action at all. After about 30 seconds the computer powers down and then powers back up. This time the system enters into POST and boots normally.
This behavior also occurs when telling the computer to re-start from within the OS.
I Believe (but am not positive) this behavior started when I changed the RAM settings. The RAM settings were set to auto, however I discoverd that I was experiencing random memory erros. This lead me to look at the BIOS settings to the RAM banks. I then took the BIOS RAM settings out of auto, and changed them to the values recommended by the RAM manufacturer. This solved the random memory errors.

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