There is a 64 bit version at the Intel site here. However the driver page <ADMIN NOTE: Broken link has been removed from this post by Dell> also contains this  statement.

Dell Update Packages (DUP) in Microsoft Windows 32bit format have been designed to run on Microsoft Windows 64bit Operating Systems.

I have the Rack version, sorry that got left off the title, so the latest version for it is A09 vs the A12 you listed, but if you extract the installer it has both 32 bit and 64 bit installers, the thing I'm wondering though is the 64 bit installer truly installing a 64 bit application or is it still a 32 bit process running in the background.  I have been unable to find anything that specifically states whether the update truly installs a 64 bit application.  

The link you sent me to at Intel does not support the 7920 Intel C620 chipset per the release notes.

Hi,

I had a similar problem on my T5820 and the problem was the old drivers from Dell. 

Then, i found the latest Intel Vroc Drivers and my problems were solved. 

I found the latest intel VROC drivers in te bellow address (Intel Website havent the latest version!):

<https://www.station-drivers.com/index.php/en/outils/Drivers/Intel/Rapid-Storage-Technology-enterprise-(RSTe)/Drivers/Intel-Rapid-Storage-Technology-enterprise--and--VROC/Intel-Rapid-Storage-Technology-enterprise--and--VROC-Drivers-Version-7.6.0.1023-WHQL/lang,en-gb/>

Hi,

I sent a private message with my solution... I tried to post my response here but it is automaticaly deleted (i think because long external link)...