Processor Clock Speed drop while using second graphic card (Nvidia) in programs and games.

I have a problem on my processor I think.

I have Acer Aspire V5 471PG with Windows 8.

My Processor clock speed is drop to 0.70GHz - 0.77GHz while i run a programs or games with Nvidia Graphic Cards but, my processor clock speed massively increase while I use intel hd 4000 graphic card. I have no idea what am i suppose to do I have been searching all over the internet and nothing change. and maybe it's cause of BIOS but I have no idea about BIOS. my System BIOS version is V1.2. I have been searching BIOS Update at Acer Driver Download and I tried to download the UEFI BIOS V2 but the installation failled because I have a different version of BIOS.

http://imgur.com/a/2eRBh

http://imgur.com/a/noTXI

Thank you.