ah hell don't tell me this. this is my problem. i bought my current GPU without realising it doesn't have enough VRAM to drive ray tracing at 4K but it's fine for everything else at 4K.
If you don't know what you're doing and have the right tools, you will break your shit.
And no, I won't tell you what they are, because if you can't figure it out it's a really bad idea (and also because I have no fucking clue, but no one need to know that part).