Hard Disk Drive Problems - HP Compaq Presario,Presario 2100 Reference Manual

If an external display does not work
Check the connections.
Press Fn+F5 in case the external monitor was disabled. (Do this three times to
return to the state you started from.)
The external monitor may not be detected. In the BIOS Setup utility, try setting
Video Display Device to Both in the System Devices menu.
If you're using a TV connected to the S-video port, you must activate the TV.

Hard disk drive problems

If the notebook hard drive doesn't spin
Make sure the notebook has power. If necessary, connect the AC adapter, and
make sure it is fully plugged into a power source and into the back of the
notebook.
Remove and reinsert the hard drive.
If the hard disk makes a buzzing or whining noise
Back up the drive immediately.
See whether the noise is coming from elsewhere, such as from the fan or a
PC Card drive.
If files are corrupted
Open My Computer, and the disk you want to scan. Select File > Properties.
Select the Check Now box under the Error-checking section of the Tools tab.
Run the virus-scanning program.
If necessary, you can format the hard disk and reinstall the original factory
software using the QuickRestore System Recovery CD.
Troubleshooting and Maintenance
Troubleshooting Your Notebook
Reference Guide 69