Intel(R) Rapid Start is a technology that is implemented by the system manufacturer directly on supported platforms. This requires the appropriate BIOS support to achieve this and the Original Equipment Manufacturer has the verify its correct operation.
If the latest BIOS and Rapid Start software are installed, and the problem is randomly solved, there might be a problem with your system to achieve S4 level.
You should check on this behavior directly with your laptop manufacturer as they may need to replicate this behavior with the same system configuration and verify that the settings they implemented are working for this system.
Ok, i will send an email to dell assistance explaining the problem and your response.