Thanks for your response, JorgeB , You were on the right track. I tried a couple of things and, finally, booted Linux from USB in the machine. It also has the same issues with the network interface. It is probably a loose contact or cold solder joint on the motherboard. If I move the cable in the socket, it eventually gets connected for a couple of seconds.
I ordered a USB-to-LAN adapter and gonna test it during the week.