It looks like there is only one 2.X version level.  So you can update from 1.X up to the 2.X level then follow the firmware upgrade guide for 2.X to 3.X to 4.X to 5.X in the current firmware download. Here is a link to all the previous versions available. downloads.dell.com/.../PowerConnect%20M6220 Don’t forget to update the boot code along with the different firmware versions. Hope this helps,
I have two dell Power connects that are on version 1.1.0.10 and i would like to update them to version 5.    When I look at the documentation and it only shows how to update from version 2.  Can i just install version 5 or do i need to do step up?
Firmware update on Dell PowerConnect M6220 