samsung rv520 with 12.1 screen brightness control??

after install the fn+up/dn adjusted the brightness slightly ( one segment ) then i updated the software via online update and it is now at full brightness…which cant be good!! when i try to adjust the brightness the screen begins to flash rapidly and nothing i can do as it freezes all accsess to anything othier than shuting down with the button any help would be appreciated.
it’s an intel i3 chip and as yet i have not been able to find any drivers that may help, regard’s J.

could this be a conflict in sys/class/backlight…?? there i have 3 files acpi…intel…and samsung…all have differant figures for brightness!!