Operating system: Windows-10-10.0.19041-SP0 64 Bits
Graphics card: GeForce GTX 770/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 452.06
Broken: version: 2.91.0 Alpha, branch: master, commit date: 2020-09-16 21:05, hash: rB27660b3cd90d
Worked: version: 2.90.1
Blender either treats DDS images like they are 100% transparent or displays it like a corrupted image file (tiles of multi colored waves)
The color picker selects the colors, the thumbnails display correctly (file browser and the image list), and Cycles renders them but Eevee and Viewport don't.
This file has a DDS image texture. and an Image Empty to display it in viewport: