Tente instalar os drivers originais do fabricante do seu adaptador de vídeo: link
Eu acabei de instalar o Ubuntu e atualmente estou sofrendo com um desempenho gráfico ruim.
Eu corri glmark2 para testar gráficos e enquanto ele imprime um bom fps no console, não parece. A animação não é suave, é instável.
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glmark2 2012.08
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OpenGL Information
GL_VENDOR: X.Org
GL_RENDERER: Gallium 0.4 on AMD RV630
GL_VERSION: 3.0 Mesa 9.2.1
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[build] use-vbo=false: FPS: 54 FrameTime: 18.519 ms
[build] use-vbo=true: FPS: 64 FrameTime: 15.625 ms
[texture] texture-filter=nearest: FPS: 58 FrameTime: 17.241 ms
[texture] texture-filter=linear: FPS: 66 FrameTime: 15.152 ms
[texture] texture-filter=mipmap: FPS: 59 FrameTime: 16.949 ms
[shading] shading=gouraud: FPS: 62 FrameTime: 16.129 ms
[shading] shading=blinn-phong-inf: FPS: 59 FrameTime: 16.949 ms
[shading] shading=phong: FPS: 61 FrameTime: 16.393 ms
[bump] bump-render=high-poly: FPS: 55 FrameTime: 18.182 ms
[bump] bump-render=normals: FPS: 66 FrameTime: 15.152 ms
[bump] bump-render=height: FPS: 55 FrameTime: 18.182 ms
[effect2d] kernel=0,1,0;1,-4,1;0,1,0;: FPS: 32 FrameTime: 31.250 ms
[effect2d] kernel=1,1,1,1,1;1,1,1,1,1;1,1,1,1,1;: FPS: 16 FrameTime: 62.500 ms
[pulsar] light=false:quads=5:texture=false: FPS: 63 FrameTime: 15.873 ms
[desktop] blur-radius=5:effect=blur:passes=1:separable=true:windows=4: FPS: 19 FrameTime: 52.632 ms
[desktop] effect=shadow:windows=4: FPS: 33 FrameTime: 30.303 ms
[buffer] columns=200:interleave=false:update-dispersion=0.9:update-fraction=0.5:update-method=map: FPS: 41 FrameTime: 24.390 ms
[buffer] columns=200:interleave=false:update-dispersion=0.9:update-fraction=0.5:update-method=subdata: FPS: 41 FrameTime: 24.390 ms
[buffer] columns=200:interleave=true:update-dispersion=0.9:update-fraction=0.5:update-method=map: FPS: 42 FrameTime: 23.810 ms
[ideas] speed=duration: FPS: 45 FrameTime: 22.222 ms
[jellyfish] <default>: FPS: 40 FrameTime: 25.000 ms
[terrain] <default>: FPS: 7 FrameTime: 142.857 ms
[conditionals] fragment-steps=0:vertex-steps=0: FPS: 59 FrameTime: 16.949 ms
[conditionals] fragment-steps=5:vertex-steps=0: FPS: 52 FrameTime: 19.231 ms
[conditionals] fragment-steps=0:vertex-steps=5: FPS: 60 FrameTime: 16.667 ms
[function] fragment-complexity=low:fragment-steps=5: FPS: 61 FrameTime: 16.393 ms
[function] fragment-complexity=medium:fragment-steps=5: FPS: 51 FrameTime: 19.608 ms
[loop] fragment-loop=false:fragment-steps=5:vertex-steps=5: FPS: 60 FrameTime: 16.667 ms
[loop] fragment-steps=5:fragment-uniform=false:vertex-steps=5: FPS: 61 FrameTime: 16.393 ms
[loop] fragment-steps=5:fragment-uniform=true:vertex-steps=5: FPS: 46 FrameTime: 21.739 ms
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glmark2 Score: 49
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Por que mesmo com boa animação fps é tão ruim? como eu poderia diagnosticar ainda mais este problema?