Help with a Foxconn motherboard

[ubieca99]

Hello everyone, I have an old socket 775 Foxconn motherboard that I'm trying to troubleshoot. I think the model number is P4M9007MB, nothing fancy really, rather a side project for fun. I bought it some time ago working, but noticed that one of the SATA connectors was pulled out and only the pins remain. One day I went to turn the computer on and nothing happened. An hour or so of troubleshooting later I had achieved nothing, so I put it in storage without the CMOS battery. Yesterday, out of curiosity I decided to plug it back in to see what had happened. You see, I wasn't going to post here since I didn't really expect anything, but suddenly the motherboard booted right up! I power cycled it to ensure that everything is actually working and it posted again! I then disconnected everything to grab a keyboard and to put some thermal paste on the CPU and after that the board never posted again, even after atleast an hour of messing around.

Here are the troubleshooting steps that I have already done:

1. The breadboard test bed is just the barebones: PSU, CPU and RAM.
2. The PSU is of good quality and known working, since it was in my main computer.
3. RAM is also of good quality and known working.
4. I have two CPUs, both tested and working.
5. Everything is properly connected, I reconnected everything atleast three times.
6. Clearing of the CMOS does nothing and the jumpers are set correctly.

What I have observed so far:

1. The CPU does get warm and eventually hot, causing the board to shut down.
2. The board is responding and is able to be power cycled by shorting the front panel connector.
3. The north- and southbridge are also getting warm.
4. Connecting a keyboard and turning the computer on does not flash the keyboard lights.
5. Removing the RAM does not yield any beeps during power on.
6. Disconnecting the 4-pin CPU connector doesn't make the board beep during power on.
7. Flexing the board or the RAM makes no difference, that or I wasn't flexing it enough or on the right spots.

Any help would be gladly appreciated. I would love to eventually assemble a whole computer out of it, if it ever works again.

P.S I feel like I have to clarify this again. I would have not bothered with any of this and would have officially declared the motherboard dead, if it hadn't randomly posted fine two times. That makes me think that the problem is somewhere else and it might even be repairable.

 

[Pentium4User]

Hello everyone, I have an old socket 775 Foxconn motherboard that I'm trying to troubleshoot. I think the model number is P4M9007MB, nothing fancy really, rather a side project for fun. I bought it some time ago working, but noticed that one of the SATA connectors was pulled out and only the pins remain. One day I went to turn the computer on and nothing happened. An hour or so of troubleshooting later I had achieved nothing, so I put it in storage without the CMOS battery. Yesterday, out of curiosity I decided to plug it back in to see what had happened. You see, I wasn't going to post here since I didn't really expect anything, but suddenly the motherboard booted right up! I power cycled it to ensure that everything is actually working and it posted again! I then disconnected everything to grab a keyboard and to put some thermal paste on the CPU and after that the board never posted again, even after atleast an hour of messing around.

Here are the troubleshooting steps that I have already done:

1. The breadboard test bed is just the barebones: PSU, CPU and RAM.
2. The PSU is of good quality and known working, since it was in my main computer.
3. RAM is also of good quality and known working.
4. I have two CPUs, both tested and working.
5. Everything is properly connected, I reconnected everything atleast three times.
6. Clearing of the CMOS does nothing and the jumpers are set correctly.

What I have observed so far:

1. The CPU does get warm and eventually hot, causing the board to shut down.
2. The board is responding and is able to be power cycled by shorting the front panel connector.
3. The north- and southbridge are also getting warm.
4. Connecting a keyboard and turning the computer on does not flash the keyboard lights.
5. Removing the RAM does not yield any beeps during power on.
6. Disconnecting the 4-pin CPU connector doesn't make the board beep during power on.
7. Flexing the board or the RAM makes no difference, that or I wasn't flexing it enough or on the right spots.

Any help would be gladly appreciated. I would love to eventually assemble a whole computer out of it, if it ever works again.

P.S I feel like I have to clarify this again. I would have not bothered with any of this and would have officially declared the motherboard dead, if it hadn't randomly posted fine two times. That makes me think that the problem is somewhere else and it might even be repairable.

I can only think of is bulging caps can cause this. look at your capacitors and see if any have bloated tops like this https://www.geeksinphoenix.com/blog/post/2013/08/11/How-to-check-your-desktop-computer-for-failed-capacitors.aspx if so you will have to replace thing with new ones. or there maybe hair/dust may be in the socket causing something, it happen to my friend lga 775 board dog hair was in the socket and it would post 1 time the not then sometimes will.

 

[ubieca99]

I can only think of is bulging caps can cause this. look at your capacitors and see if any have bloated tops like this https://www.geeksinphoenix.com/blog/post/2013/08/11/How-to-check-your-desktop-computer-for-failed-capacitors.aspx if so you will have to replace thing with new ones. or there maybe hair/dust may be in the socket causing something, it happen to my friend lga 775 board dog hair was in the socket and it would post 1 time the not then sometimes will.

They don't appear to be bulging, but they can still be bad i guess. The socket is clean.

 

[Pentium4User]

I can only think of is bulging caps can cause this. look at your capacitors and see if any have bloated tops like this https://www.geeksinphoenix.com/blog/post/2013/08/11/How-to-check-your-desktop-computer-for-failed-capacitors.aspx if so you will have to replace thing with new ones. or there maybe hair/dust may be in the socket causing something, it happen to my friend lga 775 board dog hair was in the socket and it would post 1 time the not then sometimes will.

They don't appear to be bulging, but they can still be bad i guess. The socket is clean.

If they are not bulging then they are ok.

 

[ubieca99]

What makes you think like that? Their capacity can still be degraded even though they don't appear bad. I've personally seen capacitors that appear okay but still have extremely high resistance values or are dead shorted altogether.

 

[Pentium4User]

What makes you think like that? Their capacity can still be degraded even though they don't appear bad. I've personally seen capacitors that appear okay but still have extremely high resistance values or are dead shorted altogether.

You can go ahead and test and see if any are bad, it but 99% of the time when electrolytic capacitors fail when they are bulging, rarely do I every see dead electrolytic capacitors fail not bulging they either bulge on top or on bottom. If you seen capacitors fail like that then they must be a really trash brand. I've worked on 30+ boards and never had or experience an bad/shorted cap that not bulging.