The pic shows the label on a desktop pc power supply... I understand the DC outputs like 3.3, 5 (circled red) and 12V, but I've never noticed the +5VSB (circled purple) before.
Please can someone enlighten me as to what that is?
I believe the "+5V" part means the same as it does elsewhere. The "SB" part probably stands for "Stand-By" which would mean a 5V supply that is on even when the rest of the power supply is off. It's used to maintain memory or power the power switch.