Hi aurora1098,
The system shutting down randomly could be because the HDD is not correctly seated.
Please check if the HDD is detected in the BIOS. To go to the BIOS page, tap F2 repeatedly during start up. This will take you to a blue screen, which is your BIOS page. Once you are here, please check if the primary hard-drive is being detected.
If the HDD is not detected, please remove the HDD and reseat it back again. If the HDD is now detected in the system please follow the steps below to check if the Hardware is working as designed.
Please run the Hardware Diagnostic using the following instructions:
1. Turn the computer off >turn the computer back on
2. At the Dell logo screen, start tapping the F12 key a few times until you see the One Time Boot Menu appear.
3. At the one time boot menu press the down arrow key to highlight Diagnostic, then press Enter to begin the PSA diagnostics.
4. Please make a note of any error codes listed.
You have also mentioned that the recovery disk wont work. Please do let me know, what is the error message you get.
I hope you find this useful.
Do write for further assistance
Thanks and regards,
Senthil S
#iworkfordell.