When a computer hangs after requesting the current time and date, what is most likely the cause?

When a computer hangs after requesting the current time and date, the most likely cause is that the CMOS battery has failed. The CMOS battery powers the motherboard's CMOS chip, which stores system settings such as the date, time, and hardware configuration. If the battery is depleted, the system may be unable to access or retrieve this critical information, resulting in a failure to provide the current date and time. This can lead to the system hanging during the boot process or when the time and date are requested, as it struggles to function without this essential data.

In contrast, while a faulty power supply could cause system instability, it is less directly linked to the specific issue of hanging when requesting the date and time. A corrupt operating system could lead to various problems, but a hang specifically in this context is more indicative of a CMOS issue rather than a corruption of the OS. Lastly, a malfunctioning hard drive would typically affect data retrieval and storage operations, but would not usually cause an immediate hang specifically tied to time and date requests. Thus, the failure of the CMOS battery is the most plausible explanation for this scenario.