Ok, done.

code/modules/modular_computers/computers/machinery/modular_computer.dm

@@ -48,26 +48,28 @@
 	if(cpu)
 		. |= cpu.emag_act(user)
 
-/obj/machinery/modular_computer/update_icon()
-	cut_overlays()
-	icon_state = icon_state_powered
+/obj/machinery/modular_computer/update_icon_state()
+	if(cpu?.enabled)
+		icon_state = icon_state_powered
+	else if(stat & NOPOWER || !(cpu?.use_power()))
+		icon_state = icon_state_unpowered
 
+/obj/machinery/modular_computer/update_overlays()
+	. = ..()
 	if(!cpu || !cpu.enabled)
 		if (!(stat & NOPOWER) && (cpu && cpu.use_power()))
-			add_overlay(screen_icon_screensaver)
-		else
-			icon_state = icon_state_unpowered
+			. += screen_icon_screensaver
 		set_light(0)
 	else
 		set_light(light_strength)
 		if(cpu.active_program)
-			add_overlay(cpu.active_program.program_icon_state ? cpu.active_program.program_icon_state : screen_icon_state_menu)
+			. += cpu.active_program.program_icon_state ? cpu.active_program.program_icon_state : screen_icon_state_menu
 		else
-			add_overlay(screen_icon_state_menu)
+			. += screen_icon_state_menu
 
 	if(cpu && cpu.obj_integrity <= cpu.integrity_failure * cpu.max_integrity)
-		add_overlay("bsod")
-		add_overlay("broken")
+		. += "bsod"
+		. += "broken"
 
 // Eject ID card from computer, if it has ID slot with card inside.
 /obj/machinery/modular_computer/proc/eject_id()