HP Probook 4520s Need Bios Mod

hello guys,

I am user of HP ProBook 4520s

Properties:

i5 460m (Intel HD Graphics) and the AMD Mobility 5470

I recently updated the bios but after update (F.20 to F.21)

I did not see switchable graphics in bios

AMD graphics card in the device manager and only the looks, Intel graphics card does not seem so permanent "display driver has stopped responding and has recovered" getting the message in Windows 7

also do not return to the old bios

Many thanks in advance for your help my friends