I have bought one of these cheap I2C OLED displays on Aliexpress. Just 4 wires, SDA, SCL and Power.
It works pretty well but I have a strange issue when I power the Arduino up.
Sometimes, the display does not seem to "boot". I mean that the Arduino sketch is running, but nothing is displayed.
After a reset, or pluging/unpluging the programmer, the display starts to work.
I am using U8Glib with the included examples.