Does anyone know if the new SP4 uses pulse width modulation (PWM) to dim the screen? This can cause eye-strain for some people like me. PWM is a cheap/crappy way to control the brightness of a display. You can do a test here: Blur Busters UFO Motion Tests Focus on the moving vertical lines with the SP4 at 40% brightness or below. Is the moving line one "solid" blur or can you see any separate lines within the blur? If it is the latter, there is PWM dimming.