I have installed windows 8 on my HP laptop with AMD6770M graphic card but driver is not being supported by it.How can I resolve it?
You need to either wait or accept the penalties that come with using unsupported hardware.
Have you tried the beta driver?
Are you using the dual graphics mode, with both Intel and AMD graphics hardware?
You are probably looking for an Intel+AMD Switchable Graphics driver.
In that case, you may wish to read: Win 8 AMD Switchable Graphics FAQ: (by Intel/AMD 3000 + 6770M owner)