What database is installed on the server, do you use the database?
Have you made necessary firmware updates?
Generally it is a fresh server… just with MS Windows na IO meter installed.
I didn't made any updates.
Problem has been resolved.
Problem was casued by RAID conroller itself. I have migrated data to another node, then insalled Win Srv perfromance was the same arround 50MB/s. I had to reconfigure RAID 50 to RAID 10. Dont know why but when RAID 50 was used, WR and RD was arround 50, but with RAID 5 150 and 590 MB/s. Now I have a raid 10 and performance is arround 450 - 500 MB/s.