Vulkan is a new graphics API by Khronos Group, who helped make the original OpenGL API that DOOM runs on. It's said to be far more efficient, and utilize your GPU better.

When launching DOOM, after this update, you should be given a menu to choose between OpenGL or Vulkan. If your game launches as normal, however, simply go to your settings, go to ADVANCED under VIDEO, and select the GRAPHICS API option to switch to Vulkan.

Alright, well, an important note is that Vulkan won't perform on a GPU with anything less than 2GB of VRAM. Also, at this time, Windows 7 users will need even more VRAM if they're on Nvidia GPUs. This may change in the future.

If your system DOES have enough VRAM, you may have a problem with Vulkan itself. Vulkan is included when you install the drivers for your GPUs now.

You have two options for uninstalling Vulkan.
1) Uninstall the Vulkan Run Time Libraries from your Programs And Features section of your Control Panel.

2) Hunt down the VulkanRT folder in your Program Files (x86) folder.

C:\Program Files (x86)\VulkanRT

If the folder exists, I suggest you just delete the whole cluster. Then try and find some files pertaining to it in System32. This is necessary for cleaning up Vulkan for a new install, it is not a joke.

C:\Windows\System32

Sort by name, and scroll down to the V section, until you find all the files with vulkan in the name. Delete them all.

Once you have done one (or both) of the options, it's time to reinstall.

Now, find and run the graphics driver for your vendor. In my case, I ran the latest AMD Radeon Crimson drivers, v1.6.72, and deselected everything EXCEPT for the VulkanRT install. I then went through with it. From there, DOOM should now launch! But for safety, go to the VulkanRT folder in your program files, and try running "vulkaninfo" to see if it works. If you get an error about vulkan-1.dll, you need to try uninstalling Vulkan again.

Alright, the other answer is to revert back to OpenGL. For that, head to your Saved Games folder inside your user folder, id Software, DOOM, and base.

C:\Users\<YOUR USERNAME HERE>\Saved Games\id Software\DOOM\base

Open DOOMConfig.local using Notepad or Wordpad, or whatever text editor you prefer.

Use the Find function (Ctrl + F) to locate the line "r_renderapi" and then change the number to 0. 0 refers to the OpenGL API, 1 is to the Vulkan API.

Save the file and close it. Then try running DOOM again. If it worked, you should be running the game again in OpenGL!

If you're looking for a third answer, then this might be of some benefit. There's a bit of software called Display Driver Uninstaller. What it is, is pretty self-explanatory. It uninstalls and wipes past and current display drivers installed on the system. Now, you'll want to be careful and have your drivers on hand for a quick install...

http://www.wagnardmobile.com/?q=display-driver-uninstaller-ddu-
Download DDU from the link above, and run it. It'll ask you to consider rebooting in Safe Mode. This is not necessary, but it is recommended. Launch into the client, and you'll be given 3 options, and a text box.

THE TEXT BOX IS VERY IMPORTANT. This box informs you of all the drivers the program detects is installed on your PC. I didn't realize it, but I actually had 4 drivers from my 7770 that were also contributing to a long boot time.

Your options are

• Clean and restart
  
• Clean and do NOT restart
  
• Clean and shutdown

Each option fits its own purpose, but I highly recommend you clean and restart. Again, make sure you have your drivers on hand, whether by CD or from the hard drive.

The clean-up will complete, and when your computer comes back, you'll find it's all scrunched up. This is expected, as you no longer have your graphics drivers installed. Note that this will not uninstall the Vulkan files, so you'll need to do that on your own.

Install the drivers, and see how things change.

id, you have a FANTASTIC game here. Keep it going, and let's hope Quake Champions doesn't disappoint!