Just took apart a generic 350W ATX SMPS, with no label except a bar code with the text 'Made in Thailand' and some test/inspection stamps. It could be an OEM SMPS for Dell, HP, Acer, ...
It's well made, with decent-sized capacitors on both the primary and secondary side, and no inductors or capacitors have been omitted. The auxiliary power supply is a small 50Hz iron-core power transformer and bridge - that's more durable than the small flybacks that are more commonly seen. The unit is fairly heavy in comparison to the lightweight units with fake ratings.
However, the electrolytics are mostly Arcon capacitors, and most on the secondary side have bulged and leaked - 4700uF,10v & 3300uF,10v on the +5v rail (replaced with 2 x Nichicon PW(M) 3300uF,10v); 2 x 2200uF,10v on the +3.3v rail (replaced with Rubycon YXG 5600uF,6.3v and 1500uF, 6.3v); a 2200uF,10v on -5v rail and a 1000uF,10v on the primary side (both replaced). +12v and -12v rails look OK, with no bulging caps - all small caps and 16v and higher-rated caps look fine.
Everything works fine now, but I'll keep an eye on the remaining caps to see what happens. One of the ironies of the electrolyte failure on the Taiwanese caps is that it's retarded by a high bias voltage - not many failures have been reported for caps handling 12v or higher. Almost all the failures have been for caps biased at Vcore (~1.5v to 2v).
It's well made, with decent-sized capacitors on both the primary and secondary side, and no inductors or capacitors have been omitted. The auxiliary power supply is a small 50Hz iron-core power transformer and bridge - that's more durable than the small flybacks that are more commonly seen. The unit is fairly heavy in comparison to the lightweight units with fake ratings.
However, the electrolytics are mostly Arcon capacitors, and most on the secondary side have bulged and leaked - 4700uF,10v & 3300uF,10v on the +5v rail (replaced with 2 x Nichicon PW(M) 3300uF,10v); 2 x 2200uF,10v on the +3.3v rail (replaced with Rubycon YXG 5600uF,6.3v and 1500uF, 6.3v); a 2200uF,10v on -5v rail and a 1000uF,10v on the primary side (both replaced). +12v and -12v rails look OK, with no bulging caps - all small caps and 16v and higher-rated caps look fine.
Everything works fine now, but I'll keep an eye on the remaining caps to see what happens. One of the ironies of the electrolyte failure on the Taiwanese caps is that it's retarded by a high bias voltage - not many failures have been reported for caps handling 12v or higher. Almost all the failures have been for caps biased at Vcore (~1.5v to 2v).
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