dell vostro 14 3000 (3400)

hello this is my laptop i got confused for its upgrade i searched and some where they said the maximum ram is 8gb and another said its 16gb so i wanted to ask what s the maximum ram it can upgrade to and i searched my ram speed is 2666mhz but the upgrade ram in the site says the rams are 3200mhz can it hold 3200mhz or is there a ram compatible with mine.