HD7850.
I'll try to be more specific. In VMM i press delete all modes, afterwards i press import from file, i choose my modelines file which doesn't include 256x240@53Hz, Then i press install, everything seems to be ok, even in arcadeosd it doesn't list that resolution, but after i restart the pc the resolution comes back, as if it wasn't deleted at all.
What's even more weird, like i've said before, is that even if i simply delete all modes without installing new ones, all of them would come back after a restart.
I installed crt emudriver exactly like stated in your guide.
Is there anyway to fix this without reinstalling? I don't mind tweaking things in the registry if needed.