Review on 🔹 MakerFocus 6pcs I2C OLED Display Module 0.91 Inch Blue SSD1306 OLED Screen Driver 3.3V~5V for Arduino by Cody Howard

One screen worked very well to be honest I overstretched it fiddling with my circuit. The second worked at 5 volts for 5 seconds but then went out, brightened, dimmed, brightened then turned off but got very hot. After researching a lot of online information, reviews, FAQs etc. it seems that 4k7 resistors are not required for the Arduino Pro Mini (clone) as they have internal pull-up resistors for pins A4 and A5 if they are not mounted directly to finish . Pencils. In any case, it also doesn't look like not using those pull-up resistors has anything to do with whether or not the screen is actually toasting, so I'm 90% sure it was just a bad block . I made a voltmeter just to save and showed 4.5 within operating range. Maybe hook it up to an Arduino so that in the future it's a bit farther from the 5V wall supply and needs to buy more to test. (sigh) I guess that's part of the job. All in all these little guys have a 50% success rate so far as the first case was entirely my fault.