AWS Create a raid0 volume from two ephemerals. Can be run on startup with diskpart /s diskpart.txt

diskpart.txt

select disk 1
convert dynamic
select volume 2
delete volume
select disk 2
convert dynamic
select volume 2
delete volume
create volume stripe disk=1,2
format quick recommended label="My Label"
assign letter d
exit

Note that the initial volumes are not necessarily available on boot. You may have to wait 20 seconds or so