I had 3521 Insp. with by default Win8 in it. I wanted to install Win7 therefore formatted complete laptop including system recovery 
. Then by changing boot option from UEFI to Legacy ,I installed Win7 may be without recovery .
Now I want to install Ubuntu (along with current OS), but it is showing me NO OS detected & all 1 TB space as unallocated.
Is it due to recovery problem, boot option problem... because whenever I change boot option to UEFI from Legecy , it shows no os or disk detected ..something like that.....
Please help..
thanks in advance..!!!