Comment réinstaller ubuntu 14.04.1 en dual boot avec windows 8.1

voici ma config si cela peut vous-aidez:

Windows 8.1 ‎(X64)‎
System install date: 5/27/2016
Processor
Intel Core i3 clocked at 1.70 GHz
Processor frequency measure (core0): 1.70 GHz
Number of cores: 2 physical, 4 logical
Processor socket: Socket 1168 BGA
CPU Temperature (core 0): 49 °C
Motherboard
TOSHIBA ZSWAA 1.00
Serial number (motherboard): *
SKU Number: PSCLUC
Bios version: 1.40
Date: 11/27/2014
Chipset
Northbridge : Intel Haswell-ULT
Revision ID: 0B
Southbridge : Intel H8x/P8x
Revision ID: C1
Memory
6 GB total memory type DDR3 to 798.14 MHz
Memory timing: 11.0 clocks-11 clocks-11 clocks-28 clocks-1 TT
Memory chip Samsung of 4 GB
Maximum frequency: 800 MHz
Max bandwidth: PC3-12800
Memory chip Samsung of 2 GB
Maximum frequency: 800 MHz
Max bandwidth: PC3-12800
Graphics card
Intel(R) HD Graphics Family
DirectX version installed: 11.0
Core clock: 500 MHz
Harddrive
SSD KINGSTONSV300S37A120G of 111.79 GB SATA III
Firmware: 608ABBF0
SATA version: SATA Rev 2.6
Serial number: 50026B775B02B717
HDD Temperature: 27 °C
Power time: 2474 hours
Harddrive TOSHIBAMQ01ABD075 of 698.64 GB SATA II
Firmware: AX0A4M
SATA version: SATA Rev 2.6
Serial number: 54PTCADOT
HDD Temperature: 29 °C
Power time: 8571 hours
Network
Realtek PCIe FE Family Controller
Adapter type: ethernet
Bluetooth Device (Personal Area Network)
Adapter type: ethernet
Anchorfree HSS VPN Adapter
Adapter type: ethernet
TAP-Windows Adapter V9
Adapter type: ethernet
Microsoft Wi-Fi Direct Virtual Adapter
Adapter type: IEEE 802.11 wireless
Qualcomm Atheros AR956x Wireless Network Adapter
Adapter type: IEEE 802.11 wireless
LogMeIn Hamachi Virtual Ethernet Adapter
Adapter type: ethernet
VMware Virtual Ethernet Adapter for VMnet1
Adapter type: ethernet
VMware Virtual Ethernet Adapter for VMnet8
Adapter type: ethernet
Software Loopback Interface 1
Adapter type: Loopback
Multimedia cards
Intel Corporation 8 Series HD Audio Controller
Keyboard
PC/AT Enhanced PS/2 Keyboard (101/102-Key)
Mouse
Pixart Imaging, Inc. Optical Mouse (USB OPTICAL MOUSE)
Synaptics PS/2 Port TouchPad
Screen(s)
Generic PnP Monitor
Manufacturer: SAMSUNG
Maximum resolution: 1366 x 768
Screen size: 15.3" (34 cm x 19 cm)
Manufacture date: 12/31/2011
Aspect ratio: 16:9
Video input type: Digital Signal
USB peripheral
Pixart Imaging, Inc. Optical Mouse (USB OPTICAL MOUSE)
Supported USB version: 1.10
Turtle Beach Turtle Beach PX22
Supported USB version: 2.0
Toshiba Corp. Qualcomm Atheros AR3012 Bluetooth 4.0
Supported USB version: 1.10
Chicony Electronics Co., Ltd
Supported USB version: 2.0