I am using a LENOVO B575e with BIOS version HPET18WW(1.03) (OS is win7_64 - it is not secure boot).
I am not able to enter the BIOS with any combition of keys enter, del, esc, F1 .. F12, with and without fn pressed. It is not possible to enter the boot menu either. So I am just able to boot from HDD. Standard is F1 for BIOS and F12 for boot menu.
I tried the BIOS update utitility from the Lenovo support site - but it doesnt work ( "The process does not recognize this system. The process has been canceled")
After removing the battery, the BIOS says "System CMOS Checksum bad. Real Time Clock Error - Check Date and Time settings. Press Esc to continue or F1 to enter Setup". I am now able to enter the bios by pressing F1. But I am not able to enter the boot menu. After setting the system clock I am no longer able to enter the BIOS
After removing the HDD I was able to boot from CD. So I was able to use the BIOS update utility for CD, which canceled with an error.
Note that I am not able to boot from CD when a HDD is connected.
Thanks for your help,