My laptop keeps on crashing. It is an Asus Republic of gamers laptop with Intel core i7, the OS is win7 premium, the ATI mobility Radeon graphics is HD 5870, 1 terabyte storage, and 8GB Ram. If I were to play a high graphic game it would randomly crash and show a black screen with gray lines overlaying, I have to manually turn off my laptop to make my laptop go back to normal. I do not know what is wrong with it and I hope I can fix this problem as soon as possible.
I think I need to dust the inside with compressed air.. Or maybe the thermal paste is degraded and isn't transferring heat to the heatsinks. Because I do not feel any air/heat coming out of the breathers (Or whatever you call it)
Definitely sounds like a GPU/driver issue, unless you are noticing the extraction fans running very loud/fast and the wrist-pad/keyboard getting too warm.
Do you have the most up-to-date drivers installed for the 5870? Did the problem occur with prior driver(s) or not? If yes to the first question and no to the second, try rolling back the driver to a previous working version OR revert to the recommended driver from ASUS's website for your laptop model.
There are several threads (by checking Google) that show older G-series ASUS laptops, in particular the G73 model not playing nicely with certain ATI/AMD drivers/CCC installed beyond what's on ASUS's website. This may require an updated BIOS download/install, in order to run newer AMD drivers for the 5870, if they exist...
Lastly (or firstly), try connecting your laptop to an external monitor and see if the issue repeats... There are also several threads on this being a potential issue; laptop screen/panel failing.