i will install windows vista 32 bit do I need to switch OS mode to CSM and UEFI mode?
Why would you install Vista 32 bit? Install Windows 7 x64, using the way I described in my last post. To summarise it, you need to do the following:
-Insert your Windows DVD into the drive
-Reboot your laptop from Windows 8.1
-Boot into the UEFI firmware settings
-Enable "Legacy Option Rom" or "Compatibility Support Mode / CSM".
-Save and exit setup and reboot your PC, booting the Windows 7 DVD
-Install windows to "partition e"
-When you get to the initial WIndows desktop, install your drivers for your computer, then do a reboot and go back into the setup and disable Legacy oprom/CSM
That is about as clear as I can make it. I have solved this issue on my machine and replicated it with 3 different install methods. Try giving it a go. If need be I would be happy to help out over Teamviewer (you would need a different PC to use Teamviewer video chat while we work on the one you are trying to dual boot)