[ Solved ] Question about iaStorF.sys.

Hello,
I didnt know this website and Im really impressed by the great work made and all information available here, so my sincere congratulations to you.

After having read quite long in the forum information about ACHI drivers, chipset and so on,
yesterday, I made a clean install of Win 7 and 8.1 (dual installation ) on my GA-X58A-OC ( X58 / ICH10R ) using a Crucial MX500 SSD configured as AHCI.

I installed manually 64bit Intel RST(e) AHCI/RAID Driver v11.7.4.1001 on both operative systems as I read this version was the recommended one for my chipset.

In Win 7 if I examine ACHI driver I can see iaStorA.sys and iaStorF.sys.

But in Win 8.1 if I examine the ACHI driver there is only iaStorA.sys , but it says nothing about iaStorF.sys ( or at least I havent found it ) and I thought F one was always needed when RST(e) installation.

My questions are :

Does that mean the ACHI driver isnt installed properly on Win 8.1 and really should appear iastorF.sys ?
Do you always need iastorF.sys when using a RST(e) driver?
If so, should I need a modded driver?


Thanks a lot.

@Sempa :
Welcome to the Win-RAID Forum!
Here are my answers:

  1. The Intel RST(e) driver v11.7.4.1001 WHQL has been properly installed onto both Operating Systems (Win7 and Win8.1). Windows Operating Systems from Win8 up do neither need nor use the SCSI Filter driver named iaStorF.sys. That is why this driver has not been installed while running Win8.1. If you open the file named iaAHCIC.inf by using the Editor, you will see, that the installation routine is different for Win7 and Win8 (and up).
  2. Win7 needs an additional SCSI Filter driver (iaStorF.sys) for the quick “cleaning” of SCSI SSDs. Contrary to the later released Operating Systems Win7 only supports the TRIM, but not the UNMAP command, which is needed for SCSI SSDs. For details you may read >this<.
  3. No!

Regards
Dieter (alias Fernando)

All my doubts have gone, thank you very much for explanation Fernando.