What graphics card is installed in it?

Somebody else had the same error code on an R10 when they tried with a different SSD: Same error code 

They have not responded back yet on the possible solutions.

Just tried booting with no SSD (again) and get the same result. White screen with some black squares at the bottom. I wasn't getting any video at all before so this is definitely progress, but I'm starting to think the mobo is to blame.

No error codes.

This is what I get. Again, 3080 shows no video at all, neither did 680 FTW, and Quadro M5000 gives me some video but something is still wrong. It wants to work but all I get is a white screen with text that is cut off towards the bottom. The monitor in the picture is just a 24" Dell 1080P monitor, decided to use that instead of my Alienware in case some of the performance features were creating more issues.

Could you try the following: Boot order 

It looks to me, based on that error message, that it is not finding the boot device. this would typically be your SSD, unless you ordered it with a mechanical HD only.

If you use F12 you can bring up the one time boot menu to quickly select what device you wish to boot from.

I put a brand new SSD in it thinking the one it came with somehow got damaged. The Samsung EVO 970 that is in there right now has nothing on it, so it makes sense that it would give me a boot error. That said, I should still be able to access BIOS but I don't even see the Alienware splash screen on startup - will try to hit F12 right away and see where that gets me. Stand by...

Right now I have a Quadro M5000 in it because I wasn't able to get it working with the 3080. GTX 680 didn't work either. At the moment I am able to get video with the Quadro M5000 and can see some of the BIOS messages but when I try to access BIOS I get a "boot failure on device" followed by a white screen with some of the megatrends text at the bottom. Almost as if the video is partially working.

Can't get this thing to work properly...

That looks odd. I think at this point you might want to give Dell technical support a ring, see if they can help you further with this.

It could be an indication of a failing video card or some other issue they might know about.

These are the error codes for the R12.

Can you make sure that with the video card installed and all other components installed, you get no error codes?

Do you by any chance see the Alienware logo during boot-up?

Can you press F2 during pre-boot, to enter the bios to see if you get any video output when in bios mode?

Lastly, is the monitor showing any messages regarding no video cable being connected or detected?

Okay, I hit F12 and I appear to be on said boot menu but I can’t see anything because it’s all white. 

If

I move my mouse around the bottom of the screen it starts turning black. 

"It could be an indication of a failing video card or some other issue they might know about."

Not with 3 different cards and the same issue though!  Open a support ticket with Dell. 

I was thinking along the lines of maybe a bad video card initially damaged the PCIe slot, and now every other card "fails" because of it.

But yes, a support ticket would likely be the next step to take.

How can I do that if I can't see anything? I know you can flash BIOS using a flash drive but that requires access to BIOS and being able to see what is on your screen. Unless there is another way to do it using button combinations?

There is a brand new bios out for the R12, but I would not recommend to update the bios unless directed by DELL to do this. If the system is not functioning as intended it's always a bad idea to try to do a bios update.

I already have one created - will continue to work with them on it. I figured maybe there was some knowledge I could tap into on here. Thanks everyone.