My laptop is XPS 13 9360 (year 2017) with 8GB ram and Toshiba THNSN5256GPUK NVMe 256GB SSD.
I converted my SSD drive from 512 to 4K sector size. After that the BIOS (version 2.9.0) stopped seeing the drive. In BIOS settings it doesn't show up. Neither does it show in boot options. The drive still works though. I can boot off an SD card (grub running on SD) and run OS from the SSD fine.
Does anybody have similar experience?
What do you mean you converted the sector size? Sector size is a hardware-level property of the SSD itself. If you had a so-called "512e" drive that had 4K sectors but emulated a 512-byte sector layout for compatibility reasons, then I suppose there could be a firmware-level way to turn that off, but I've never heard of a 512e drive that allows that setting to be changed. Is that a thing now? But if you have a "512n" (512-byte native) drive or "4Kn" (4K native) SSD that doesn't offer emulation, then this can't be changed.
Anyhow, 4Kn drives are still found almost exclusively in enterprise-oriented offerings, so I'm not too surprised that consumer systems might not work exactly right with them.
Out of curiosity, why did you do make the change in the first place?
The drive is 4K native emulating 512. I use nvme-cli under Linux to reformat the drive.
My main motivation is performance gain which I didn't test myself. I could go back to 512 and reinstall my OS. Just want to confirm that 9360 really doesn't support 4K native drives.