Not sure where to start on this one. Yesterday I reinstalled Win 7 with a new HDD on an old Toshiba L300 laptop. The installation went well except for twice when, before the boot options screen came up, the screen went black and then showed some colours in horizontal lines or even dots. This happened so quickly I didn't have the time to take a picture of it. It would almost look like one of those old failing TV monitors. I quickly hard booted the laptop by pressing the power button, rebooted and it went into F8 mode so I chose safe mode.
I did not find the right solution from the internet
References : https://www.cnet.com/forums/discussions/laptop-sc ... blem-diagnosis-where-to-start/
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