I've had the Win 7 laptop for a few years, and it's worked faultlessly.
Now the HDMI port no longer works and seems completely dead, VGA port is ok. I've tried several HDMI cables and monitors / projectors. The laptop used to switch the screen off as soon as I plugged in a projector or monitor, that no longer happens, so it's not detecting the monitor or projector at all.
I've been trying to update the graphics drivers without success, I've tried two things:-
1. Went to Graphics device in Device Manager and pressed 'Update Driver', it told me my driver was up-to-date (even though its dated 2011)
2. I went to the Dell driver download page and downloaded the most recent Intel (R) Graphics Family driver (August 2012), but this unzipped to a GUI application that crashed.
What is the current OS installed on the system? Is it still Win 7? What is the exact system model - N5110 0r M5110? Is the video card detected in device manager? Is there a discrete video card on the system, if so, what model?
Try reinstalling the video drivers from the vendor site - Intel.com and Nvidia.com or AMD.com depending on the video card on the machine.
If you are not able to find the driver, then send us a screenshot of the device manager with display adapters expanded and I shall find the links for you.
Based on your response, we shall advise further course of action.
Also, please click my DELL-username and write me a private conversation with the service tag and your contact details(Name and Email) for case records.