Have you tried using different video drivers? what is exactly occurring? can you boot into safe mode? (hold F8 while booting)

Have you tried Safe Mode ( holding F8 while booting ) also have you Tried LKGC ( Last Known Good Configuration) For doing LKGC, hold the F8 key while booting and there you may see LKGC just select it. DO Power Drain. Check whether your Ram is detected in BIOS, if not then try to Reseat your RAM, may be the problem may with your RAM. see whether it is working, else try to reseat your Hard Disk, and check it once. If Nothing works,May be your display driver is not compatible and try to Install a New Display driver from the HP.com. TO Download and Install a Display Driver from Hp.com, log on to HP.com, There you may find " Softwares and Downloads" just click on it, then provide the model no, Operating System, and select the driver you wanna Download and Install. Now check whether Your Diaplay is working or not, i hope it will work now.....! If it works, then please send me a feedback mail to : - info.prem4u@gmail.com incase if it wont work, please do mail me regarding this issue and i will send some technical notes regarding this particular issue.......! Regards, S. PremKumar.