Lenovo SYSTEM BOARDS 5B20Q15571 is compatible in the following Models:

Lenovo 500 Series (IdeaPad)

IdeaPad 520-15IKB (81BF) Laptop - 81BF007CAU
IdeaPad 520-15IKB (81BF) Laptop - 81BF00AQIN
IdeaPad 520-15IKB (81BF) Laptop - 81BF00E3LT
IdeaPad 520-15IKB (81BF) Laptop - 81BF00KEIN