Dell OptiPlex GX270

[SysRed]

I had a client bring a Dell OptiPlex GX270, this is the model with the small form factor which takes half height cards etc. The initial problem was a simple case of bad memory as per Dells light and beep code. Or at least that is what it was reporting, having reseated the memory all was fine. The computer was returned to me with a problem with not booting into to XP, had no problem booting into Linux, BART PE off USB stick and or the CD etc, anyhow to cut a long story short re-loaded XP (clean install) The next problem was a BIOS error, something like 'vendor and IDs do not match' I personally did not see the error and when booted into XP the LAN card no longer worked, again I did not get to see this. Then the PC would not boot at all and gave a DELL light error code, which translated to 'A possible expansion card failure has occurred' there are no expansion cards installed on this particular PC. Lastly it now does not POST at all and all the DELL error lights are off, which states 'either normal condition' or 'a possible BIOS failure has occurred.

Ok, I have swapped the memory out, tried a different PSU, I have not tried a different CPU, if I remove the memory and or disconnect any of the drives I get no beep error codes whatsoever, all I ever get is the main yellow diode on the MB lit up and the keyboard light flash for a split second when powering up. Also the on/off power button remains orange at all times, where as in normal operation it turns green. I suspect it is the motherboard, I can see no obvious signs of capacitor leakage or bulging. Any ideas ?

Many thanks

 

[goombawaho]

I suspect your diagnosis to be correct. No sure of what else you can do.

Try taking it out of the case and putting it on a wood or tile surface and connect only a (known good) power supply, CPU, memory and video card (if not integrated) and see if things change. Literally - nothing extra connected (USB devices, etc., etc.) Use the "shorting the pins on the motherboard" method to start the PC instead of the front panel switch.

That eliminates everything unless you can also swap out the processor, memory and video at different times to DOUBLE CHECK those items.

Then, if no love, it's the MOBO.

 

[edfair]

Power supply and standby circuit on the M/B work together to get the green LED operating. Until this is resolved all the other suspicions are useless.

Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[SysRed]

Ed Fair post ~
Power supply and standby circuit on the M/B work together to get the green LED operating. Until this is resolved all the other suspicions are useless.

Hi Ed, very interesting, can you expand a little as i have tried a different and known PSU (as previously stated) and get the same results. Given that it looks like a degenerating problem, the board has a number of caps that aren't particularly straight and this particular board is known to have bad caps issue, i suspect it is the board. But if you can enlighten me on how best to test the PSU i would appreciate it.

Thanks

 

[goombawaho]

board, board, board, board. toast, toast, toast, toast.

 

[kjv1611]

I guess to expand on the topic, one could say that now your board is good for a very large and awkward scraper?

 

[edfair]

PSU is fine. Just wanted you to go to the heart of the problem which is standby not coming up.

I have one machine that used to take 30 minutes to get standby up. Sat there flashing yellow until it got ready. Tried to power it up last week and it has finally given up the ghost.


Ed Fair
Give the wrong symptoms, get the wrong solutions.