can a dead gpu still work with Microsoft Basic display adapter
Solution 1:
All the Microsoft Basic Display Adapter needs is a framebuffer. Basically the graphics chip can take in an image constructed by the operating system and display it on a monitor.
All this requires is the most basic graphics features, it doesn't require the graphics card to ramp up to any high power mode or any kind of 3D operation, it just needs an input, and the raster output of the graphics card to work.
If the compute (CUDA/Shader) units of the graphics card were damaged by it overheating then you could have a major section of the GPU pipeline that is broken for "normal" Windows, as it uses the GPU for desktop compositing, but can be bypassed with the Basic Adapter.
If the graphics card works for viewing the BIOS, then it will work with the Basic Adapter.
Knowing what actually went wrong is difficult to establish. It could be that one or more memory chips have failed and the card is unable to fully establish how much or what type of memory it has, the black checkerboard makes me think that one of your banks of memory on the graphics card has failed. Either the memory controller in the chip for that side has dies, or a memory chip itself is dead and has taken out the rest of the bank.
I've seen a few graphics cards that have failed and only worked in the most basic mode and refused to install "proper" drivers to use the full card functionality.