In computer circles, it has been known for a while that Dell had at least a batch of bad motherboards on Optiplex GX270 machines. It affects several form factors that have different MB's inside. The actual failure was caused by the electrolytic caps near the power regulation section (and presumably filter caps for the +5v rails) bursting on the top & leaking. Today I had the first failure of an Optiplex GX280 with the exact same problem. I've got 100 of THESE machines, but that's my problem, not yours....
Anyway, I've been looking at the replacement MB's coming from Dell to see what's changing. The voltage value is the same 6.3V, so it doesn't look like they chose caps with too little voltage margin. The values are the same, so they're not increasing the capacitance. They are, however, replacing Nichicon brand caps with Rubicon brand caps. All the failures have been Nichicons. All the replacements Rubicon. Dell seems to have made a change.
Not to besmirch the name of Nichicon, but I just thought it was an interesting piece of information that will affect my cap buying habits, at least. Thought you guys might find this of some value in the FWIW department.
Grace and peace,
Steve
This happened to many manufacturers, the reason was the formula for the liquid goop in electros was stolen (industrial espionage!) from a major manufacturer BUT!! one component was missing (a corrosion inhibitor I think) & next thing you know, there are a billion electros from the mainland that were little timebombs. A lot of VERY expensive Panasonic video gear was ruined by this... you couldn't make up this stuff!!!
The upside is, it's pretty obvious when it happens, you see liquid oozing out of the cap. Unfortunately you then have to replace ALL the electros, & a lot of this stuff isn't designed to be repaired easily.
Reminds me of the time 25 years ago a friend was manufacturing computers & got a "great deal" on cheap Mexican tantalum bypass caps.... oh dear.......
Thanks for the info.
And Dell won't replace them until they fail, so now I get to do regular visual inspections of all the machines to try to catch them leaking before they actually fail. :P
So then, do you know if this affects other brands?