dell studio 1749 - ati hd5650

hello , i have 17 inch dell laptop 1333mhz ram running at 60c gpu when oc ed to 760 mhz core 970mhz memory.
i have edited vbios sucessfully and i increased core to 600mhz to oc further using msi afterburner.
I would like to go 1,05 or 1,1 volt gpu to overclock further, as i said my temp wont go higher than 61 when playing dirt2 or black ops at high detail at 760/970mhz
i know how to unpack bios and i know how to use radeon bios editor but rbe wont do the job.
If anyone knows how to change voltage by editing bios then please help.
i can see voltage changes when i change freq...

also i want to upgrade cpu to i7-620m 3,66ghz from ebay , they said it can handle 1333mhz ram as original handles at 1060mhz.
is it good to buy this cpu from ebay?

i have also moded gpu heat sink to get better heat transfer.

 

also i would like to know if i can oc my current i5 cpu.
no help from setfsb..

 

if it is not possible to go higher in bios than 1v then im going to need help on mainboard modification. 1,05 to 1.1 is needed
i am sure ic can change from 0,9 to 1v itself