Under normal circumstances, there is no problem that computer software and hardware can't solve. According to my analysis, the original hard disk of the old computer should be mechanical, and the second one should be solid after installation and expansion. If there is no reinstallation system, the system disk is mechanical, and the old computer hard disk will not show no signal when it is completely removed. It should be a hardware problem, as long as it is not hardware damage, it can be solved by itself. As long as the memory card, graphics card, etc. There should be a poor connector contact, or you can try to remove the master clock from the motherboard.
Soft jumper in solid-state setting of master-slave disk cap of mechanical hard disk