SteamOS installation - can't boot

[Wanderer]

I'm trying to install SteamOS since ~5 hours and I'm still at the very beginning, since my system refuses sustained to boot from my usb drive, so any advice is highly appreciated.

Here's what I did/tried so far:
- I downloaded the zip file from here (expert installation): http://store.steampowered.com/steamos/buildyourown
- I unzipped it directly to my freshly FAT32-formatted usb device. I tried to different devices from different vendors, both consisting of one single MBR partition. One device has 2GB, the other one 16GB of space.
- I entered the bios of my machine (it fulfills the SteamOS requirements by far), its bios is an UEFI.
- I chose the UEFI-entry for my usb device.

Now, my screen gets black for a second, then I'm back in my bios.
I installed Win7 in UEFI mode on the same machine.
Also, Lubuntu starts fine in UEFI mode using the exact same usb devices. I have also tried the non-UEFI entries.
I tried different usb slots on my machine, on the front as well on the back.

I know, that there are different ways, that there exitsts an ISO an that several people compiled their own distributions, but that's not the point I'm looking for. The point is:
Why the heck is it not working this way?

[ProfessorKaos64]

Can you please read through the wiki below and report back after?

https://github.com/ValveSoftware/SteamOS/wiki/Getting-Started

[Wanderer]

Thank you for your answer.
I would claim I did everything right...

[Csar]

Did you try it on a USB 2.0 port on your PC?
Mine sometimes has similar issues when booting off certain thumb drives

[Styromaniac]

You need GPT instead of MBR. UEFI requires GPT.

[Wanderer]

Originally posted by Csar:

Did you try it on a USB 2.0 port on your PC?
Mine sometimes has similar issues when booting off certain thumb drives

Yes, I tried USB 2.0 and 3.0 ports.

Originally posted by Styromaniac:

You need GPT instead of MBR. UEFI requires GPT.

Have you tried this yourself? Because every source I've found so far states that the device has to be an MBR partition.

[Teddy]

Then you are misinterpreting your source. Legacy boot uses MBR, UEFI uses GPT. Period. Do not mix the two of them together on one moachine.

[Wanderer]

Okay, this will be the problem. Dammit.

To be honest, I did not double-check the information. It seems to be fairly clear stated here, that MBR is correct to UEFI-Boot SteamOS: http://store.steampowered.com/steamos/buildyourown

Anyway, thanks a lot for the tip!

[MeanCusine]

I had the same issue, glad to find the solution right away. I tried emailing some form of support dude from steam to see if they can get someone to fix that. Not sure who's job it is. 7 years ago this issue was solved but not fixed.

[PyroTiger]

wow this solved back in 2013 and terminology is still not fixed