Thank you Sujatha K.
I found my way to the video drivers thanks to you. However, before downloading: I did not see the name of my driver on the list. My Inspiron 570 lists a ATT Radeon HD 4299 in Device Manager as my graphics card --not under Video, though I understand they are the same thing. Only video cards are listed on the Dell Update page, and I don't know which to download and install. Can you help? Thank you!
Sandy