[ubuntu] Dual installation Windows 8 and Ubuntu 13.04

Hi
I installed today Ubuntu 13.04 alongside a Windows 8 installation

Installed:
Windows 8 is installed on a Samsung NP700Z5A notebook UEFI and GTP partitioned.
The system has "TWO" disks, an SSD 256 Gb and an internal "memmory disk" I used it for windows swap area totally

What I did:

I installed Ubuntu 13.04 from USB/EFi on a free partition manually assigning "/" (root) and a swap partition (sda6 & sda7)


http://elrebollar.org/images/ubuntu1...-02__15h22.txt
http://elrebollar.org/images/ubuntu13/Screenshot-1.png
http://elrebollar.org/images/ubuntu13/Screenshot-2.png

To my surprise after install the system booted to windows 8 (I wast waiting the ubuntu interface)
At the installation I select to install the grub at /dev/sda
I have no brub to select from at boot

Any good ideas?

TIA

Jago