X51, Internal hard disk not found

What operating system do you have installed (Windows XP, Vista, 7 or something different?

When was the last time your computer started without any issues?

Did you add / remove any hardware / software prior to your computer not booting?

Did you notice any other changes prior to your computer not booting?

If you have a windows operating system, you can select F8  while the computer is starting in order to get to the advanced start up menu. From there you can select the option for Safe Mode and the system will load only the necessary drivers for your computer. Then you can sign in using your user name / password (if you have one) and remove any new software that you may have installed. You can also select Safe Mode with networking and this will allow you to get on the internet. You can then browse to the Dell or Microsoft website and research to find out why your computer is not loading normally.

Another option outside of running the computer in safe mode is to select Last Known Good Configuration and this will allow your computer to start from the last point it worked properly.

It stated

Please select boot device 

UEFI: ST31000524ANS

UEFI: ST31000524ANS

Enter setup

Enter ePSA

Use arrow keys to move selection

Enter to select boot device

ESC to boot using defaults 

Thank you for such a detailed reply and the system which i have is windows 7. I did try to read the dell support page but their instructions did not match what was happening in my system. The last time it had the issues were a few months ago but it was not as major as what was happening now because I had to reboot it a few times before it started working properly so I did not take much attention to it. But as I feared the situation grew worse. I do recall changing to navida processor to something else but soon I started getting random computer freeze so soon after i changed it back and the freeze still won't go away.Before my computer started getting the 'internal hard disk drive not found' error ,whenever I boot up my computer and start to play games it will keep freezing. It even freezes if I am doing nothing on the computer.

* Restart / Power on your computer
* At the first text on the screen or when the Dell logo appears, tap F12
* What is listed there?

Yes UEFI is indeed chosen

Alright thank you so much Chris and destiny_Integration for your help. Really apreciate it

Alright thank you al much Chris and destiny_Integration for your help. Really apreciate it

* Restart / Power on your computer
* At the first text on the screen or when the Dell logo appears, tap until the message Entering Setup appears
* Boot Mode will be listed under Boot -> Boot Priority
* Press Enter on Boot Mode and the System Setup will display a warning message about changing the Boot Mode

Is UEFI chosen?

Hi Chris.  I'm having a similar problem to this one with my Alienware r3 Andromeda.  It was working perfectly fine until I decided to reset it to wipe it clean.  I just wanted to purge it because I had recently backed everything onto an external hard drive.  Midway through the reset it gave me an error and said to restart.  When it restart it went straight to a black screen that says the hard disk is not detected and to reseat.  I opened it up and pulled out the hard drive and put it back in and the problem still persists.  I've been on forums all day and also tried to see if it would start at all with the hard drive unplugged and I couldn't even get to the Bios.  I got on the phone with Dell but my warranty is up.  Last thing I did was run the preboot system assessment and  everything workls fine.  I'm a student so I really need my pc for school and I'm also broke so it's really difficult for me to get another pc when I'm struggling to afford food.  Any help would be greatly appreciated

Hi Chris.  I'm having a similar problem to this one with my Alienware r3 Andromeda.  It was working perfectly fine until I decided to reset it to wipe it clean.  I just wanted to purge it because I had recently backed everything onto an external hard drive.  Midway through the reset it gave me an error and said to restart.  When it restart it went straight to a black screen that says the hard disk is not detected and to reseat.  I opened it up and pulled out the hard drive and put it back in and the problem still persists.  I've been on forums all day and also tried to see if it would start at all with the hard drive unplugged and I couldn't even get to the Bios.  I got on the phone with Dell but my warranty is up.  Last thing I did was run the preboot system assessment and  everything workls fine.  I'm a student so I really need my pc for school and I'm also broke so it's really difficult for me to get another pc when I'm struggling to afford food.  Any help would be greatly appreciated

Its an x51 r3.  Whenever i would go to the properties section on the computer it would say Andromeda after the R3. I  wasn't using dell recovery.  I went to windows update and security for the "reset".  Halfway through is when it crashed.  I did the thorough epsa scan and it says everything is working fine.  Says the HDD is fine.  I unplugged the cables and they seem to working fine as well.  Everything was working perfectly fine before I did the reset and now nothing.  I really don't think its a hardware failure because it was working fine before. I did upgrade that pc to windows 10 from windows 8.