I am having a very confusing issue with my Compaq Presario CQ42 Notebook.
After working fine for a long time, it was only booting to a black screen with the usual solid power and wireless light, and flashing caps lock light. This occured when I had turned it on with HDMI connected.
I tried all the usual tricks, remove/reseat RAM, try different RAM, reseat HDD. Also opened it up, checked all connections, including CPU, removed it and refitted it to be sure it was sitting right.
Pressing F8 got it to boot on a rare occasion but to no avail. After many attempts, I got it to boot after pressing random keys I cannot recall and installed the latest bios update and utility once I got into Windows.
I checked it over, including restarts, tried HDMI when it was running. And the problem did not occur.
All worked fine for most the day. To be sure I connected the HDMI with the power off, and powered it on. Nothing but a black screen. Again I went through all the reseating procedures etc, to no avail. I have tried every idea I could think of with no luck. Pressing F8, F10, holding Win Key and B, a hard reset, removed CMOS battery, but no luck at all.
I am very confused as what to do now as it it stuck with black screen again, and I have no idea how I got out of it the first time. I know after the first time that all hardware is working.
Any help would be greatly appreciated.