Is PCIE x4 bootable for NVMe SSD under Linux

[dukla2000]

There is another issue I found,  lxde and mate desktop have some conflict with nvme disk.
When I use  LXDE release image, after I login, the system hangs when MVMe disk is inserted (the red led on my PCIe -M.2 adapter is turned on, then off).
When I use minimal release image,  MVMe disk is recognized (the red led on my PCIe -M.2 adapter is turned on and keeps on)
Based on minimal release image, I installed Ubuntu-Mate-Deskstop and LightDM.   The systems works after I log in, but MVMe disk is not recognized (the red led on my PCIe -M.2 adapter is turned on, then off).

I have no desire to try MATE, but my thoughts:

1) LXDE release is known to be less usable than minimal, stick to minimal.

2) If you boot a newly flashed minimal then hopefully you can see the NVMe? I suggest lsblk and sudo blkid all the time to check what is happening. If you add the Mate-Desktop and NOT lightdm presumably you login to a console prompt? Check again. Then add lightdm etc.

I do not have the Pine64 PCIe riser for my NVMe (got some other no-name) so have no insight what is correct LED behaviour, sorry.