Viewports broken on RX 580 Blender was working fine until recently (I can't pin point what happened). I have not knowingly changed any settings in Blender or on my PC in general.
I've been working with Blender daily and hadn't noticed the change since most of what I was doing was in Cycles Render View, which does seem to work.
Here's the problem.
Doesn't matter if it's a file I open or a default object on a fresh file.
In Object mode, if I add any object (example monkey), then switch to wire frame, I get an outline of the object only, no wire frame. Solid view seems to show correctly. Material Preview only shows a filled outline, the fill color is the same as the grid color, but applying a color does not make any difference. Render View EEVEE shows a filled outline, not a render, and the fill color disappears as I rotate the object. If I switch to Cycles, it seems to be ok.
I was using Blender 2.90, and hoped that switching to 2.91 would resolve, but it's exactly the same. I also tried going back to 2.8 and got the same result. I then looked at my graphics card RX 580 which recently did an update...I reverted back to the previous version, but to no avail.
I'm out of ideas, and cannot figure out if this a Blender issue, a hardware/software issue....or if I inadvertently clicked something. I've looked through Blender settings repeatedly but can't see what could be wrong.
I did see a post here from another user who is having the exact same issue, and he/she uploaded a youtube video showing their issue. I would have preferred to comment on theirs, but this forum doesn't let me, so I had to load my own questions.
[UPDATE Dec 4-2020]
I did a system restore back 1 month (to ensure no new updates were present), tested and Blender was working fine (V2.90). I began re-installing updates one at a time and test after each.
Summary of results - All Windows updates installed to current, Blender works fine.
Radeon updates - v20.9.2 (driver v27.20.12031.1000), Blender works without issue.
Radeon update 20.11.2 &amp; 20.11.3, Blender is broken.
Started having the same problem just after a Radeon update[I think 20.11.1]  (AMD RX580 8gb),
GPU viewport rendering is broken(was using portable Blender folder, tried installing updated Blender and still no fix).
After some googling found some people were having similar problems and decided to leave it for a couple of weeks in case of a fix-patch.
No update patch yet but I tried switching to &quot;High Quality Normals&quot; and it totally worked for me!
TEMPORARY FIX: Render Properties &gt; Performance &gt; High Quality
Hope this can help others too.