Hey mate,

How did you tried to clean ?
Its hard to say what kind of liquid or what cause this . Anyway as C164,163,169 &190 its capacitors and theyre same as C211,210,169 &170 or C54,56, 94&95 . As for C31, C32, C103, C104, C106 its harder cause there is no reapeting elements

Interesting info, cheers. Cleaning process today was vinegar + stiff antistatic brush on the worst areas (including those bubbly parts of the traces you can see in the last pic), then water rinse, then a general clean with contact cleaner.

Looks like its been sitting out in the open where water can get to it, them bubbled traces look like corrosion bubbles.

you can also check continuity of corroded vias, some of them are probably cut.
very strange corrosive attack...

whaka wrote on 2022-01-23, 14:44:

you can also check continuity of corroded vias, some of them are probably cut.
very strange corrosive attack...

Ya know .. it kinda looks like someone spilled a drink into the case, it reminds me of a friend who used to sit their cup of coke on top of their tower PC which had vents in the top ... well he used to do this till one day he up ended the drink into the vents. Totaled the PC but the corrosion spots on the back of this card remind me of soda dripping onto it while it was running, some of them do look like some kind of sticky residue.

Unless its Flux residue from someone trying to repair it previously.