Detailed Troubleshooting & Results - Motherboard

[Rapideye]

Hi all,
Ive set this post up from a previous one.
This way i can make it eaisier to explain properly, and slowly work through the troubleshooting process on motherboards.

The Problem
I was using A Pentium 4 Prescott 2.8Ghz skt478 in a Shuttle XPC: FB61R v2.1, not realising it didnt support this cpu and that it would damge it.
It worked flawlessly for a year, and then realising that i should be using northwood based cores (the MOSFETS wre roastingly hot), I purchased a 2.6Ghz Northwood and installed it only to find the board wouldnt boot.
The lights and fans were on but nobody was home.
I worked thru all the usual troubleshooting routines, but i just could not get the northwood to boot (its working fine in my currnet DFI board).

So, i gave up and returned to using the prescott/shuttle again, However i did find a BIOS update, but it didnt give prescott support (research has revealed that BIOS updates alone will not give compatibilty, FMB 1.5 will).

This BIOS flash didnt work, and the system then refused to boot with either CPU installed.
This was getting frustrating.
I resorted to hotflashing the shuttles SST chip in my DFI, as they are the same model of eeprom.
The Hotflash went fine using UniFlash BUT.........
CARELESSLY, i put the chip in the shuttle socket the wrong way.
You may aks how i did this, as the EEPROM socket are keyed in the corner.
Well, i cracked the plastic socket when i removed the EEPROM, and being in an awkward place, and being to careless, i replaced the newly flashed EEPROM in right side up, wrong way round :-(
This was almost instantly realised, wehn i booted up, nothing happened, and i ran my finger over the EEPROM....it was boiling hot!.............oops

So, i ordered a nwly flashed SST EEPROM chip, installed and now im back to where i was.......the lights and fans are on but nobody is home.

What ive tested

The EEPROM (SST 49LF004B 3.3v) and socket has been tested, the VDD for the chip on pin #32 = 3.35v
This was measured against Pin #16, the VSS ground and atx ground.
This looks good as its a 3.0 -3.6v chip.

Components:
CPU = Tested, Working
RAM = Tested, Working
GFX = Tested, Working
HDD = Tested, Working
PSU = Tested, Working

- PSU has been tested with multimeter, the numbers look good from the PSU side, all rails are displaying correctly.

What next?
So now im down to the motherboard,
I understand that the MOSFET's and/or Capacitors could be blown/faulty and this is where i need some help.
What method should i next use for the process of elimination?

Heres the board in question:



If you can help me out on this process of elimination, that would be superb and greatly appreciated.
If possible, please try not to stray too much off topic, id like to keep it specific, with suggestions and results posted only.

Thanks in advance

[arneson]

Re: Detailed Troubleshooting & Results - Motherboard

That is a realy good picture, but am I correct to say that is not your board?
I don't see the cracked prom chip carrier.
I will also assume that you forced the beveled side now and not the writing side down.
This would have taken a huge amount of force, hammer?, to do.
That style socket is not happy when broken and the board underneath, also not happy.
So in fact, if as stated you are back to square one, I would not waiste another second. IMHO

[Rapideye]

Re: Detailed Troubleshooting & Results - Motherboard

That is a realy good picture, but am I correct to say that is not your board?
I don't see the cracked prom chip carrier.
I will also assume that you forced the beveled side now and not the writing side down.
This would have taken a huge amount of force, hammer?, to do.
That style socket is not happy when broken and the board underneath, also not happy.
So in fact, if as stated you are back to square one, I would not waiste another second. IMHO

My board is almost identical, my FB61 v2.1 has a few extra 1000uF caps around various places, the pic is of a FB61 v1.0
The EEPROM socket is cracked, but only on the plastic bit, the conatcts are all perfect, and its recieving voltage.
it didnt take a hugs amount of force, the keyed corner was the part that was cracked, so dropping it in the wrong way wasnt hard.
As it was right under the PSU with an inch clearance, i didnt have much room to see, i was over confident having done hotflashing many times.
If i had of removed the PSU, i wouldn't have made the mistake of doing this.

That set aside, the EEPROM is no longer a problem, i just thought id mention it to clarify the events as they happened.


Ive found a site on testing caps:
http://www.repairfaq.org/REPAIR/F_ca...ml#CAPTEST_004

Anybody have any experience testing them with a multimeter?

Thanks

[gonzo0815]

Re: Detailed Troubleshooting & Results - Motherboard

I have fliped some flash devices too sometimes, i burned my fingers on it
But again, it was working again after reseating the right way.
If the contacts are fine, there should be no problem if the plastic carrier is broken.

[Rapideye]

Re: Detailed Troubleshooting & Results - Motherboard

SUCCESS!

Ive just went straight ahead and recapped the bloody thing.

Thats one good recap under my belt.

I got a full set of caps direct from shuttle (thanks rafal), installed them, burn in tested for 12 hours.

Volts are stable, board temps are a little high, i think the cooling fan now needs some attention.

thanks to all.

[yanz]

Re: Detailed Troubleshooting & Results - Motherboard

blue, black, and green ost. the more color the merrier

congrats on your sucesfull recapping project! i wonder what caps did shuttle sent to you?

[Rapideye]

Re: Detailed Troubleshooting & Results - Motherboard

They sent me OST caps, a complete set.
They did replace the Blue 10v 1500uF with 16v 1500uF though.
Its been running fine now for a few weeks, i have noticed some noise coming from the PCB during disk/USB operation, the board temps are a little high too.
I have also noticed that the PSU readings are getting jumpy, 3.3v and +12v, within .05 ranges.