best practice with RAID0 configuration - to keep all of them in separate drives i.e. tempdb, mdf, ldf, backups Database size - 145GB
Currently our database mdf file, tempdb, backups are in D drive and log files are in C drive.
Can we go for the below configuration:

D drive - tempdb, E drive - mdf, f drive - backups, C drive - logs

or

D - tempdb, E - mdf ,F - logs &amp; backups

We have 26 servers with full recovery model which works 24/7 for our clients.
and more than 100 for other clients with Simple recovery model which works only 9 to 6.
Currently, we have available only 4 hard drives to allocate with this configuration C, D: Mirrored (RAID 1) and E. Can we fit our database all files in this kind of configuration or avoid RAID 1?
Front end application crashes frequently during the day time and inaccessible during night time as maintenance tasks runs which are database integrity, rebuild/reorganize, backup and delete old files.
Could someone please help me with best suitable approach for this?
From performance and safety point of view, 1st solution is better (if you have 4 physical disks available).
For sure you need to separate as soon as possible backups from mdf files in differents disks: in case of a disk crash you lose both the DB and the backup!