Mon minecraft crash quand je le démarre

Bonjour, j'écris parce que mon minecraft crash a chaque fois que je le démarre.
Ils m'écrivent ce message: ---- Minecraft Crash Report ----
// Don't be sad, have a hug! <3

Time: 27/07/15 18:35
Description: Initializing game

org.lwjgl.LWJGLException: Pixel format not accelerated
at org.lwjgl.opengl.WindowsPeerInfo.nChoosePixelFormat(Native Method)
at org.lwjgl.opengl.WindowsPeerInfo.choosePixelFormat(WindowsPeerInfo.java:52)
at org.lwjgl.opengl.WindowsDisplay.createWindow(WindowsDisplay.java:247)
at org.lwjgl.opengl.Display.createWindow(Display.java:306)
at org.lwjgl.opengl.Display.create(Display.java:848)
at org.lwjgl.opengl.Display.create(Display.java:757)
at org.lwjgl.opengl.Display.create(Display.java:739)
at ave.ap(SourceFile:534)
at ave.am(SourceFile:363)
at ave.a(SourceFile:310)
at net.minecraft.client.main.Main.main(SourceFile:124)

A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
at org.lwjgl.opengl.WindowsPeerInfo.nChoosePixelFormat(Native Method)
at org.lwjgl.opengl.WindowsPeerInfo.choosePixelFormat(WindowsPeerInfo.java:52)
at org.lwjgl.opengl.WindowsDisplay.createWindow(WindowsDisplay.java:247)
at org.lwjgl.opengl.Display.createWindow(Display.java:306)
at org.lwjgl.opengl.Display.create(Display.java:848)
at org.lwjgl.opengl.Display.create(Display.java:757)
at org.lwjgl.opengl.Display.create(Display.java:739)
at ave.ap(SourceFile:534)
at ave.am(SourceFile:363)

-- Initialization --
Details:
Stacktrace:
at ave.a(SourceFile:310)
at net.minecraft.client.main.Main.main(SourceFile:124)

-- System Details --
Details:
Minecraft Version: 1.8.7
Operating System: Windows 7 (x86) version 6.1
CPU: 3x AMD Athlon(tm) II X3 450 Processor
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
Memory: 99047840 bytes (94 MB) / 158208000 bytes (150 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
Launched Version: 1.8.7
LWJGL: 2.9.4
OpenGL: ~~ERROR~~ RuntimeException: No OpenGL context found in the current thread.
GL Caps:
Using VBOs: No
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: []
Current Language: ~~ERROR~~ NullPointerException: null
Profiler Position: N/A (disabled)

Pouvez-vous m'aider? Merci!!