On the Razer Deathadder wired there is 4 on-board memory profiles, these are empty at the start.
Trick is to go into synapse, make a profile, name it and set values as desired.
Right on the top where it says the name of your profile, the dropdown menu where you can select between any and all profiles you have made, to the right of it there is a small icon, looks like a sim card for phones.
Click on it and to the right there will appear the empty profiles of the razer mouse, below those you will see the name of your own recently made profiles, all you have to do is drag your profile to one of the empty slots.
Doing this the mouse now has 1000hz polling rate without synapse installed and it keeps all settings after reboot and connecting the mouse between different computers.
I feel like this is something that would have been very helpful if specified with the mouse in a quick-install guide or something.