To make it easy, install GRUB Customizer Type these into terminal emulator : Code:

sudo add-apt-repository ppa:danielrichter2007/grub-customizer
sudo apt-get update
sudo apt-get install grub-customizer

Open GRUB customizer, make a new GRUB entry.

Open 'Sources' tab, type these : Code:

set root='(hd0,4)' `search --no-floppy --fs-uuid --set=root e1f9de05-8d18-48aa-8f08-f0377f663de3 linux androidx86/kernel root=UUID=e1f9de05-8d18-48aa-8f08-f0377f663de3 quiet androidboot.hardware=generic_x86 SRC=/androidx86 acpi_sleep=s3_bios,s3_mode initrd androidx86/initrd.img

set root='(hd0,4)' : Change the (hd0,4) to partiton Android x86 is installed. The hd0 means sda, so if you install it to sdb, it'll be hd1 and so on. The hd0,4 means the partition number, in my case, hd0,4 means sda4. So if you install it on sda6, it'll be hd0,6.

    --set=root e1f9de05-8d18-48aa-8f08-f0377f663de3 : The random number here is the UUID of partition Android x86 is installed You must change it to correct UUID, you can easily got UUID by creating new entry in GRUB Customizer then go to Options tab, then select the 'Linux' option in dropdown. You'll see partition dropdown, select your partition. Open the source tab, you'll see the UUID there.

    androidx86/ : The root of Android x86 Change it into your Android x86 root. You can see what's your Android x86 root by navigating to Android x86 partition, and you'll see a folder name started with 'android', that's the root of your Android x86

    androidboot.hardware : Your device, of course. Note : If you're using Android 2.3 - 4.0.3, change it to androidboot_hardware Here's the list of hardware :

generic_x86 : If your hardware isn't listed, use this
eeepc : EEEPC laptops
asus_laptop : ASUS laptops (supported ASUS laptops only)