Full compatibility with Lenovo IdeaPad 320/330/520 & Chao5000 series notebook models; 4-Pin PWM brushless fan, intelligent speed control for low noise & efficient heat dissipation; Brand new factory fan, pre-tested to eliminate abnormal noise and stall issues; Exact original mounting bracket & wiring layout, direct plug-and-play replacement; Durable wear-resistant bearing, long service life to stop laptop CPU overheating