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Dell 400SC Motherboard Capacitor Problems

This page documents some problems that I have run into with two Dell 400SC Server motherboards.

Motherboards that were built in a specific time period seem to be developing problems with electrolytic capacitors that are failing sometime after the first year of service.

Similar problems were found with a variety of motherboards in the 2000-2001 timeframe. Even though the problems are similar, it seems that the problems with the Dell 400SC are unrelated to the large quantity of poor quality capacitors that were on the market in 2000-2001. This batch of problems seems to be more of a specific quality control problem at a single manufacturer during a particular time period.

See these links for some more details on the problems the sometimes occur with electrolytic capacitors on modern motherboards, where high frequency currents seem to push the envelope of what these devices can be expected to handle:

Here are some photos of the problematic capacitors on my motherboards: Motherboard 1 is Revision A02 - it did not exhibit any noticeable problems when running; however, the capacitors look worse than my other motherboard, as a couple of them are 'oozing' whatever is inside those things.

400SC Rev A02 Bad Capacitors - Photo A
Revision A02 - photo A
400SC Rev A02 Bad Capacitors - Photo B
Revision A02 - photo B
400SC Rev A02 Bad Capacitors - Photo C
Revision A02 - photo C

Motherboard 2 exhibited numerous strange failures - out of memory conditions, refusing to run programs due to inadequate permissions, reboots, etc. I spent a significant amount of time trying to fix these problems, assuming that they were 'malware' related. After trying to diagnose and/or fix the problem with several anti-virus and spyware removal utilities, I happened across the thread on the Aaltonen forum describing the capacitor problem. When I inspected the motherboard, sure enough the capacitors were bulging.

400SC Rev A03 Bad Capacitors - Photo A
Revision A03 - photo A
400SC Rev A03 Bad Capacitors - Photo B
Revision A03 - photo B
400SC Rev A03 Bad Capacitors - Photo C
Revision A03 - photo C

And this is a photo of a plastic standoff that Dell uses to attach the heatsink bracket to the motherboard/motherboard-tray. I damaged it when preparing the motherboard for shipment - I think that it's probably still OK to use.

Heatsink Bracket plastic standoff
Heatsink Bracket plastic standoff