[REQUEST] Bios mod for DELL 15R 5521

Hello.

I would kindly ask you if you can mod this bios for me, i would like to disable the Radeon 8730M and use only the integrated Intel HD4000.

My system: DELL 15R 5521
Bios type: Insyde H2O
Bios version: A12
Bios link: Dell 15R 5521 BIOS Version A12

Sorry but I must flash it from DOS, because I've put on my laptop OSX 10.9.2 (for this way i must disable the Radeon 8730M) so if you could teach me how to do that would really be appreciated!

Thanks in advance