Dell U3011 no display after a few minutes

[mike-s]

Yet another reply to say thankyou for the info that led me to fix a U3011. I bought it off FB Marketplace based on the symptoms the seller described & everything that was described in here.
Like many others, the root cause was a failed TOP266VG causing the 5v rail to drop to 0.1v or less and the 24v rail to drop to 6v after running for a handful of minutes and overheating itself to oblivion.
For future reference for anyone trying to fix one of these, I used a thermal imaging camera to track the failure location and quickly identified the TOP266VG as the culprit.
When the monitor was first plugged in the temperature would rapidly increase to 45'C and keep climbing. When the TOP266VG got to 54'C the power would cut out.
At one point I saw it climb as high as 72'C

Once I replaced it the temperature would sit at around 26-32'C in a ambient 22'C.

[Andre_]

For the PS-2202-3-HF power supply of the Dell U3011 30" monitor:

After investigation of the power supply i found out that the 817 opto coupler of the feedback loop was broken, which than fried the TOP266 power chip.

See attached picture for the location of the components.

After replacing both, the monitor worked fine again.

[Kinetic]

Another beneficiary of this thread coming to say thank you!! Re-flowed the gray, rectangular capacitor and VOILA!, monitor working again!