No startup on motherboard

[Solder Boy]

Hi all.. I have a motherboard ( I can get the name of it in a minute) that doesn't power up at all even though when I check for voltage at the power switch terminal it shows 3.1 volts.

Did an initial check of the caps for ESR all seem to be good.. would a capacitance meter also help in this matter?

Also would this be a sign the voltage regulator on the board has gone south?

[Solder Boy]

Re: No startup on motherboard

I didn't see the edit function so I'm adding new information. The board in question is an Asus P4S533 Rev 1.03

[Leopard]

Re: No startup on motherboard

Caps can be bad even if they visually don't look like it. If possible, test if the board boots with another PSU to rule out a possible PSU problem (though excessive ripple from a PSU can kill caps faster, especially the bad branded ones). Post the brand of the caps on the motherboard.

[Solder Boy]

Re: No startup on motherboard

The bigger caps around the power supply connectors are made by Taicon.. can't really tell easily what the smaller caps are.

[pfrcom]

Re: No startup on motherboard

I have had no success trying to resurrect SiS chipset based boards like your P4S533

If it does not boot, I try rewriting the firmware in its BIOS chip with an EPROM burner

If no boot after that, do not waste any more time, straight to the junk pile

[Solder Boy]

Re: No startup on motherboard

Thanks for the info.. never heard of an Eprom burner though, how do you flash the bios if you can't get the board to light up?

[shadow]

Re: No startup on motherboard

An EPROM burner is a device used to program EPROM's (for example a BIOS chip).

With an EPROM burner you can take out the BIOS chip from a motherboard and reload/reprogram the BIOS onto the chip.

Therefore if the BIOS somehow got corrupted, it can be resurrected without having to boot the affected system.

[pfrcom]

Re: No startup on motherboard

BIOS chip is a data storage device which holds firmware (low level software) that makes hardware work

If the BIOS chip is socketed, it can be removed and rewritten externally, using an EPROM burner

Willem programmer is an inexpensive example of an EPROM burner

Note: Willem is designed on Open Source software principle, usually supplied with little documentation

[tazwegion]

Re: No startup on motherboard

The other alternative is 'hot chiping' though you need an identical board to perform this unorthodox solution... essentially you fire up the working motherboard and pull it's BIOS chip (while still powered up) then CAREFULLY insert your corrupted chip and overwrite it's CMOS data

[KeriJane]

Re: No startup on motherboard

Hello.

One thing that nobody seemed to mention....

Check the CMOS battery!

Certain boards/chipsets will not boot with a dead CMOS battery.

Example: The Shuttle FT61 board based on the ATI RS300/IXP150 chipset.

Symptom: Fans start, lights on, no video or disk activity.
Recapping the board had no effect. Before scrapping it I checked the battery- 0v. Replaced battery- works great!
So all those OST caps were FINE .

Have Fun,
Keri