Can I install Windows 7 64-bit on external eSATA SSD hard drive as my boot OS?

I would like to install on internal, but I also need to run RAID for my data drives for redundancy.  I want to us SSD for my OS drive for obvious reasons (speed).  But the TRIM command to clean up SSD's is not functional through RAID controllers.  I'm wondering if Windows 7 will install and operate from a eSATA drive?  My BIOS will let me select the eSATA as a boot drive, but I've seen posts that mention Windows OS will not allow you to install on external drives.  I also understand the eSATA is 3Gb/s but I'm wondering if there are any differences in external enclosure bandwidths? 

Or maybe the native Windows 7 ATA-TRIM command does work through RAID controllers? 

Alternatively, I could have all drives setup for IDE, then use Windows software RAID controller, but I have to believe that would significantly slow down my data drives, which is less than ideal too. 

Any clarity on this would be appreciated.  I don't want to go down a $700 path and lots of time if the result is no good.

Question Info

Last updated December 6, 2019 Views 21,774 Applies to:

Hi Jeff_Elucidate,



You can install Windows 7 on ESATA external drive. Plugin the drive to your computer, go to BIOS and make sure that ESATA drive is set as the default device to boot. And during installation of Windows 7 install the required drivers and you must have your Windows 7 installed on ESATA drive.

You can refer the link below: 


Swati K- Microsoft Support Engineer

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