Depending on the actual model of the old Compaq, you can enter the CMOS/BIOS setup by pressing on the a special
function key or key combination during Power-On Self Test (POST),
before the operating system loads. During POST, the BIOS
usually displays a prompt such as:
Press F2 to enter Setup
keystrokes that will access the BIOS Setup are F1,
For older Compaq computers, like the Deskpro 286 or 386, you must
place the Diagnostics diskette
in the A: drive, and then
restart the computer.
For newer Compaqs, like the Prolinea, Deskpro XL, or Presario, while
the cursor is at the top right corner of the screen during bootup,
press the F10
The hard drive controller can not be replaced without replacing the motherboard. Incidentally, there are old PCI sundcards that has an IDE port and can be configured to replaced defective on-board IDE port.
If your concern has not been addresses after completion of the above procedures, you may need to seek the services of a qualified professional.
Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information.
Good luck and kind regards.
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