How to install after windows 8.1 with MBR partition

Hi dear all,
I have a laptop, which has a 500GB hard disk and with MBR partition, and I install my windows8.1 on it, but I left ~75G unused which I would like to use it for OpenSuse13.1. Now I have 2 USB, one is Gnome Live 13.1, another is standard DVD install ISO.

I tried to insert Gnome live 13.1 and no problems, it recognized my unused 75G partition, and recommend my Linux partition as below:
/dev/sda6 → swap
/dev/sda7 → /
/dev/sda8 → /home

I cancelled this installation and try with DVD iso, and now i get an error when I try to use my 75G unused partition as below:
Your system states that it requires an EFI boot setup, since the selected disk does not contain a GPT disk label YaST will create a GPT label on this disk. You need to mark all partitions on this disk for removal.

I would like to keep my windows and create a dual boot system, but I am stuck here. anyone please give me some suggestions? thank!

While others may give you an explanation about the message and mayb a solution, my question is about these two phrases of you:
“…I left ~75G unused …”
“… I try to use my 75G unused partition …”
It is one of both. Either that 75 GB is unused space, or it is in a (or more) partitions. For the installation process, disk space is onlly free/unused if it is not partitioned. The installer can not decide by itself if a parttition is unused or has contnets that is worthwhile to be kept. That is something only you as human owner know.

It is better to leave disk space free, that is "not partitioned. Then the installer will concentrate on that part of the disk to bring you a proposal for it’s usage.

You need to configure your motherboard to boot from DVD in legacy (BIOS, CSM, whatever it called - non EFI) mode. Live media support only legacy boot, but DVD supports both legacy BIOS and EFI; apparently default configuration of your system is to try EFI boot first.

Alternatively it may be possible to select it in motherboard boot menu. Please consult your motherboard manual how to …

On Fri, 25 Jul 2014 16:06:01 GMT, bashee wang
<bashee_wang@no-mx.forums.opensuse.org> wrote:

>
>Hi dear all,
>I have a laptop, which has a 500GB hard disk and with MBR partition, and
>I install my windows8.1 on it, but I left ~75G unused which I would like
>to use it for OpenSuse13.1. Now I have 2 USB, one is Gnome Live 13.1,
>another is standard DVD install ISO.
>
>I tried to insert Gnome live 13.1 and no problems, it recognized my
>unused 75G partition, and recommend my Linux partition as below:
>/dev/sda6 → swap
>/dev/sda7 → /
>/dev/sda8 → /home
>
>I cancelled this installation and try with DVD iso, and now i get an
>error when I try to use my 75G unused partition as below:
>Your system states that it requires an EFI boot setup, since the
>selected disk does not contain a GPT disk label YaST will create a GPT
>label on this disk. You need to mark all partitions on this disk for
>removal.
>
>I would like to keep my windows and create a dual boot system, but I am
>stuck here. anyone please give me some suggestions? thank!

Please do the following:


---------------------
parted -l

gdisk -l
---------------------

Abd paste the results in code block (#) in the advanced editor mode.

I expect that Win 8.1 converted your disk to gpt/uefi and the install DVD
detects that. openSUSE DVD can handle that just fine though if the DVD
drive is set in BIOS to boot in the EFI mode.

?-)