Dell Optiplex GX280 issue

ally_uk

Hi Guys recently started tinkering with a Optiplex GX280, Pentium 4, 2.8GHZ the machine is displaying a interesting fault where the fan will spin up real fast I mean this sounds like a Plane taking off, It spins really fast and literally sounds like the machine is either going to take off or explode.

I have replaced the CPU fan with a well known working one and the machine is displaying the same issue. The problem occurs when you turn the machine on. I have also changed the PSU.

I had the Machine running a good few hours without the problem occuring, installed windows and everything was fine until I shut the machine down. The PC hangs on shutdown so I did a manual turn off and when I powered up again I had the Fan kicking up a fuss again. When this happens the output on the monitor dies and the monitor led just blinks on and off.

Can anyone shed some light on this situation? Dead board? the machine was donated to us so I'm not really holding my hopes up.

Plantwiz

Is this the mid-tower? Or one of the SFF models?

If mid-tower, there are not many fans in the unit. Are you certain the noise is from a fan? Maybe the Optical drive or HDD?

But then you state is is displaying a fault? So, I don't know? What error message is displayed again?

nel

Have you checked the capacitors on the mobo? the 280's are well known to have a design fault where the capicitors explode and cause erratic behavior with the PC as a result of a mobo issue. If you look at the capicitors the heads (the top bit) should be flat like a coin. If the tops are leaking or are not flat (usually a Tent shape head) then the capicitors have gone and cause motherboard issues. We have had plenty of machines out of warranty and dell have actually still replaced the mobo as it was a design fault on there end.

We have around 700 280's which must of been the pc batch from hell - the amount of issues we've had is unbelievable. Another popular issue with them is dodgy psu's where you power on the machine and eventually the PC power button flashes amber as if in standby mode causing you to force a restart. U can tell this by looking at the PSU fan as it stops operating and causes overheating.

mrmcmint

Nel is correct about the capacitors. We have loads here that have done that.
Sounds like a dead board to me, inaccurate temp readings are causing it to shut down by the sounds of it.

techster79

As a former DCSE, I can confirm it as a motherboard issue. A similar problem cropped up on Dell Latitudes where the sensor was blown and reporting 255 degrees F. The fan never stopped running no matter what was happening due to the bad temp reading. You could run a Dell Diagnostic off of the HDD partition to confirm, or off of resource CD.