When was the last time you have a visual check on your server internally? Some might have heard about the capacitor plague but if you have not, and you have owned the server for many years already you should do a visual inspection on your server motherboard immediately. The capacitor flaw was reported as early as 2002, and a surge of such complaints in 2010 with the higher than expected premature failure rate of aluminium electrolytic capacitors with the non-solid or liquid electrolyte capacitors from some Taiwanese manufacturers. The capacitors failed because due to a poorly formulated electrolyte with water-based corrosion effect.
Direct visual inspection is the most common method of identifying these capacitors which have failed because of a bad electrolyte. Failed capacitors may show one or more of these visible symptoms:
a. Bulging or cracking of the vent on top of the capacitor.
b. Capacitor casing sitting crooked on the circuit board, as the bottom rubber plug has pushed out.
c. Electrolyte leaked onto the motherboard from the base of the capacitor or vented from the top, visible as crusty rust-like brown in colour deposits.
e. Detached or missing capacitor casing. Sometimes these vents do not open, a failed capacitor will literally explode, ejecting its contents violently and shooting the casing of the motherboard board.
When this happens, the capacitors no longer able to serve their purpose on filtering the direct current voltages on the motherboard, as a result of this failure is an increase in the ripple voltage that the capacitors are supposed to filter out. This causes system instability. Capacitors with high ESR and low capacitance can make power supplies malfunction, and causing further circuit damage. On the server, the CPU core voltage or other system voltages may fluctuate and possibly with an increase in CPU temperature as the core voltage rises.
Even though there are not many cases nowadays and seems to have receded since 2013, I still urge you to have this inspection done quickly especially for servers was manufactured before 2010. Apparently, I’m still seeing many of these branded servers are prone to this plague in operation when I was walking around the data centres.