First of all. I do not know if this is the correct forum to post this, and im sorry in advance. Im on a Pavilion dm4 ,Windows7 , i5 and ATI Mobility Radeon Premium Graphics which supports microsoft Directx11. Recently when i just rebooted my laptop, the resolution was extremely large. Trying to solve things, i right clicked my desktop and clicked screen resolution. I put it at the highest resolution but it was still the same. Than an error came up saying "No ATI graphics driver is installed or the ATI driver is not functioning properly. Please install the ATI driver appropriate for your ATI Hardware.I also can not adjust the brightness of my screen. I am at a loss of what to do. Please, please help me. Thanks in advance.
The first possibility is that your graphics drivers got corrupted. You can download a free driver cleaning software such as http://download.cnet.com/Driver-Fusion/3000-2086_4-7574..., and delete all your graphics drivers. Reboot your laptop, download new drivers from the ATI website, and install them. Let us know if that doesn't fix your problem.
I suppose you'll have to find out what graphics card you have. There may be a sticker on your laptop that give you the model. Otherwise, you can open the start menu, type in "dxdiag", go to the display tab, and it should tell you your graphics card. Use that to download the appropriate driver.