Tried both, just hangs, either way
UPDATE....
Some drivers must have changed in new loader ! Here is what I did...
Just started with blank hard drive. Installed ( DSM_DS3615xs_5022.pat ) got the system up and running. Shut system down, Stuffed in new usb drive with ( XPEnoboot_DS3615xs_5.1-5055.1.img ) Chose Install Upgrade. Managed to get to Diskstation login, But sysnology assistant does not find device. Not showing any IP etc on screen. Guess I cant use this boot image on my system.