the c1e setting when on allows the cpu to throttle back when not in use but synology software does not like it and if you manage to boot it usually freezes or hangs when the c1e even occurs
there are a few options depending on your setup
this is my setup
4 hard drivers the 1st one is solely for xpenology the boot partition, all files and programs go on there the other 3 hdd are where i store all my files moves,tv etc
now if all yours are on one hdd then you are limited you could buy or source a cheap hdd and install xpenology on that then use linux to delete partition off the original hdd