hardware changes log

[killabyte]

hi guys, im a victim from hardware hackers, recently one of my imacs was modified againts my will, it was downgraded from 2x2GB RAM to 2x1 GB RAM.

i dunno how did they do that, thats insane. i need to know when did it happen. i guess it was registered somewhere in a system log, i need to find the day and the hour that issue happened, so maybe i can find the culprit. please help me to find the right log file.

best

killa