CRTL & Alt did not push the BIOS verification to completion. I have to force shut down as CRTL,Alt & Del don't work. When computer restarted, cannot recognize the UEFI installed Win 8.1 in SSD drive. I have to re-sintrall Windows 8.1 and start all over. At least, the computer is not bricked that is good. In case you need to know why I have to reflash the BIOS, I was playing with CloverEFI bootloader for hackintosh. I forgot that it will write into the BIOS. It did and I cound not my Win8.1 in UEFI mode only legacy. EZFlash is safe and secure but refuse to falsh the BIOS saying I have an older version. Therefore, I thought the only way is through DOS. I don't like flashing through Windows because Winflash does not have good reputation. Luckily, we have the option /nodate meaning telling the BIOS flasher to mind his own business meaning just flash the darn BIOS for me and stop asking question. Once again, thanks @Tito. You save my day. I have to reinstall Win 8.1, optimize SSD drive etc. I will be busy for the next little while. I try to use W8.1 installer to repair Windows 8.1, it failed. Windows now is an inferior OS compare to Android and OSX. That is why M$ is in trouble because they have weak mobile platform in Windows phone. What a pity.