We've recently had a couple of IBM ThinkCentre A50s coming in all having similar problems.
When pressing the power button both the power lamp and the HDD lamp light up and the fan starts running on full speed (noisy) without getting a signal on the monitor.
I've tried leaving the PCs on for as much as 10 minutes to see if they will boot, but they're basically stuck in the same state as described above.
Has anyone heard of anything similar or have any thoughts on what the problem might be?
Your help would be greatly appreciated.