First of all, unless you are using RAID or SSD Caching, you do not need Intel RST and can uninstall it. This will tell you if it was responsible for the issue (I highly doubt it).
In previous situations with similar symptoms, the issue is usually the result of the Windows Update service installing a new version of a device driver - one that is not 100% compatible with your actual hardware. By default (read: unless you have had problems with one), you should be running the versions of the device drivers that Dell provides for you on their web site. These are the versions that Dell has fully tested. It is certainly possible that a driver update could cause issues like this (including with Intel RST).
Hope this helps,