After upgrading the power supply, what should you verify if the hard disk is not functioning?

Verifying the power connectors on the hard disk is essential after upgrading the power supply, as an improper or loose connection can lead to the hard disk not receiving the power it requires to operate. If the power connectors are not securely attached, the hard disk will not function at all, leading to symptoms such as the operating system failing to recognize the disk or the disk not spinning up at all. Ensuring these connections are properly seated can eliminate one of the more straightforward hardware issues that can arise when changes are made to the power supply.

In situations where you have just upgraded components like the power supply, it's common for connections to become loose or improperly seated, which is why checking them first is a logical step. Other aspects like BIOS settings can be relevant later, especially if the drive is not detected, but they would not influence the physical power delivery to the device. Drive formatting is also an important consideration for drive functionality but typically comes into play only after confirming that the drive is physically functional and recognized by the system. Lastly, hard drive capacity is a consideration for performance and usage but doesn't directly affect immediate functionality such as whether the drive powers on.