Sometimes it can happen, that a NetVista or ThinkCentre shows one or more indeterminable errors like:
- HDD/CD-ROM drive sometimes will not be recognized at boot time
- instead to boot there appears a "PXE Boot" - message, the computer hangs at it or feezes sometimes
- getting bluescreen sometimes, even after replacing HDD and a fresh installation of the operating system
- endless loop from POST until starting the boot sequence
- the eventmanager shows under "System" error messages f.ex. "Controller-error \device\harddisk0\d"
- display (especially grey areas) flickers for a while, if onboard graphics is used
- network-connection gets interrupted some times, or will not be recognized
- onboard network device will not be recognized anymore
- after turnng on the computer no bootlogo appears, the monitor switches into powersave mode resp. stays in powersave mode
The reason for these symptoms often are damaged electrolyte capacitors. - On closer inspection there will be found a blown upper side or a brwon coating is visible on the upper surface.
In both cases the electrolyte capacitors are damaged, so the system board needs to be replaced. Experienced users also can replace the capacitors (if out of warranty, otherwise send to repair centre to avoid warranty void)
On the attached picture there is the blown surface visible on the blue capacitors (red marked). The green marked capacitors have a flat surface and are well. The capacitor in the lower left corner is leaked (brown electrolyte on the surface)