Same problem here - 2 weeks strugle with the problem - NO FIX
Changed the ESXI HP Custom build - NO FIX
VMware-ESXi-5.5.0-Update2-2403361-HP-550.9.2.40.2-Sep2015.iso - NO FIX
VMware-ESXi-5.5.0-Update3-3116895-HP-550.9.4.26-Nov2015.iso - NO FIX
VMware-ESXi-5.5.0-Update3-3568722-HPE-550.9.5.0.33-Apr2016.iso - NO FIX
Changed the RAID - NO FIX
RAID-5 - NO FIX
RAID-0 - NO FIX
RAID-10 - NO FIX
Single SATA HDD - NO FIX
Deployed HP CUSTOMER ADVISORY - Document ID: c04760147
Removed : scsi-hpdsa-5.5.0.48-1OEM.550.0.0.1331820.x86_64.vib
Installed : scsi-hpdsa-5.5.0.36-1OEM.550.0.0.1331820.x86_64.vib ( dated June 15, 2015 )
Result : MINOR IMPROVEMENTS ( 40 -50 MB/s tops and random fails to 4-5 MB/s at copy & paste )
Curently trying with OLDER HP IMG : VMware-ESXi-5.5.0-Update2-2403361-HP-550.9.2.27-Mar2015.iso
Still no information about the result.
Any Help on this will be really great !