Hey @avathar
I'm sorry to hear your system keep rebooting whilst trying to play the game and thanks for providing your system specs. You mentioned you have already tried our "fix list" but please can you double check both of these articles here and here, so we can be sure to know which things you are referring to, and just let us know if you have done all of these.
If you still have issues after these steps, let us know here and we can create a support case for you, as we'll need to get these system files from you to look into this further.
DX Diag
MSInfo
If you would prefer to contact us via live chat, you can do so here and we can get your files from you whilst speaking to you on there.
As live chat isn't always available, you can also reach out through a private message on Twitter or Facebook if you prefer, as that will also create a case for you and we can then get your system files off you through there.
If you do contact us through one of the above options, please be clear when you mention what steps you have already done, or just provide links to those articles so they don't get suggested to you again. Also, please let us know here if you have, otherwise we will create the support ticket for you if you still need assistance.
Regarding your question about DirectX instead of Vulkan, this is something I am waiting to hear back from the game team myself about, so I have made a note of this thread so I can get back to you here about it when I have an answer from them.