Dell Vostro won't boot- goes straight to black screen with blinking cursor

What happens if you remove the hard drive?

Would that be a simple procedure?  What would be expected to happen if I'm able to do it?

It depends on the exact system model.  On most, it's easy to do.  If the system will allow you into BIOS setup once the hard drive is out of the system, it means the drive is bad and will need to be replaced.  If the same fault continues with the drive out, the mainboard is bad.

I removed the hard drive, and instead of the black screen with blinking cursor, it's a black screen with various product information, then "Media test failure, check cable" and "Exiting PXE ROM."  I can enter into setup and boot options, but it won't boot the installation DVD.  I tried putting in an older hard drive, and when I turn on the power it automatically boots the installation DVD, rather than being stuck on the black screen.  But it can't install Windows because it couldn't locate any drivers.  So can you tell me what this would mean?

It means the original hard drive is bad.  Since the system was already on Windows 10, download that and make a bootable flash drive to reinstall Windows 10.

www.microsoft.com/.../windows10

The system will already have a digital entitlement to Windows 10, so it will activate once you go online.

Thank you for your help.  I have installation DVD's for Windows 7 and 10 already, but neither of those were able to download Windows successfully with either hard drive inserted (with the bad hard drive, it gets to the end, then says it couldn't boot to the next phase of installation; with the older hard drive, it says it can't locate a driver to install Windows on).  Is there something different if the installation media is a flash drive?

What model system is it?  I.e., Vostro 5468, etc.?

Vostro 3300.  Quite old, and I think it came with Windows7.

Make sure with the Windows 10 installer that you partition and format the drive, particularly if the drive came from a system with GPT -- which the old system you have won't support.

With WIndows 7 you'll likely need to pause the install with F6, connect a flash drive with the SATA drivers on it (see below) and then continue the installation.

Go to the driver page for your system and under Serial ATA, download the Intel Rapid Storage driver - that contains what you'll need.

www.dell.com/.../drivers

Vostro 3300.  Quite old, and I think it came with Windows7.

You don't have to guess.

Go to Dell support and enter your Service Tag number and it will show the Original Configuration.

A blinking cursor in the upper left of a black screen usually means the system is looking in the wrong place for the boot files.

If it came with Win 7 it is probably not a Secure Boot system but boot the Win 10 install Media and go to Repair you computer and run the startup repair.  If you can't boot the Install Media, does it show in the Boot Device menu or what messages do you get.

If a Startup Repair type operation (and it may take a few) does not help, you will need to look at the BCD Store to see how it thinks it is supposed to boot.  I am assuming you have checked the Bios to make sure the correct device is selected a primary boot option.

I'm not really sure how to partition and format the drive, as I haven't been able to open disk management, even by command prompt.

Thank you for the advice about downloading rapid storage.  My even older laptop can't seem to read that page correctly, so I'll try it from my work laptop later this week.

By the way, when I enter into setup, under Main>Internal HDD, it says "Not present".  Does this mean the old hard drive is also bad?  Or possibly inserted incorrectly?

If the drive doesn't show in the Bios, then for whatever reason, the system will not be able to use it.  If you have the capability and the age of the system would allow for drive failure,  replacing it might be the best option.  You can replace it just for testing to confirm the situation prior to trying to recover your OS.