I’m making a custom case for BPI M2 Zero, to house the board itself, a 30x30x7mm 5V fan mounted above CPU heatsink, and Ethernet breakout board. I am planning to use low profile 14x14x6mm aluminum heatsink for CPU, and no heatsink for RAM. The case will have some ventilation holes but not many, to keep clean looks.
Is this enough, or do I need to use a larger heatsink for CPU and/or add a heatsink for RAM?
Also, is it OK to use the board with such small heatsink and no fan for a while, outside of case, to determine that it functions OK before soldering headers - or do I need to immediately add fan for cooling it?