Nvram module not working

[nveen]

Laptop: Sony vaio e series (SVE1511aenb)
Bootloader: (Chameleon/Chimera)
CPU: i3-2328m/HM76
Graphics: HD3000, 1366x768 (Vendor:intel(0x8086), Device id(0x0116))
Ram: 4gb

i patched DSDT for brightness slider it works fine but on every reboot brightness slider reset to max. so i added FileNVRAM.dylb in Module folder and restart. then i change brightness slider to minimum lavel but on next restart brightness reset to max.