Don't know if it's been mentioned - some psu's have a "hiccup" mode
where they shut down, pause and retry under fault conditions. If the
psu is marginally overloaded it may go into that mode as things warm
up.

R
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist