Haven't found anything on this searching google and the like. It's a purple zigzag pattern that is certainly fuzzy, but not like others have described. It is windows 7 pro and not sure what else to say...
I'll share that I test such by booting up any other Live OS like Linux. I don't have to know Linux. It's to see if the issue is across OSes.
If it's fine in Linux then I consider restoring the machine to its factory OS and drivers.
I can't guess the causing Problem with less info, so I am not sure the problem is with hardware or the software.
well if the software is causing Problem, then you might wanna update the graphic driver..
first, look for the driver updates through HP support Assistant, if you can’t find any graphic driver update there then try finding it with Intel driver utility.
if the driver is already latest version then try uninstalling the driver then reinstall graphic driver
I'm having a similar problem with my Dell D630 (old system) laptop due to age issues with the display card and system board/bus. I was able to reduce the problem by switching the BIOS to use the internal video adapter instead of the nVidia one.