Hi,

Thanks for all help.

>>> Lots of system output contained below <<<<

o System crashes to black screen and mouse pointer remains responsive. I have to re-boot via power off button to get back (ouch!). This is most prone when opening Firefox and sometimes Chrome. Viewing youtube video in browser can cause crash too. 

o Not sure if I can re-start cinnamon as I don't know how to in this situation.

o Google reveals this 'black screen crash' is happening quite consistently for a number of people running new installs of both LM C 17.1 rebecca and recent(?) ubuntu.

o Some basic details :
Kernel: 3.13.0-37-generic i686 (32 bit, gcc: 4.8.2) 
Linux Mint 17.1 Rebecca
Machine:   System: LENOVO (portable) product: 7661CH8 version: ThinkPad T61
Mobo: LENOVO model: 7661CH8 Bios: LENOVO version: 7LET44WW (1.14 ) date: 06/27/2007
CPU:       Dual core Intel Core2 Duo CPU T7100 (-MCP-) cache: 2048 KB flags: (lm nx sse sse2 sse3 ssse3 vmx) bmips: 7181.94 
           Clock Speeds: 1: 800.00 MHz 2: 800.00 MHz
Graphics:  Card: Intel Mobile GM965/GL960 Integrated Graphics Controller (primary) bus-I

$ apt-cache policy xserver-xorg-video-intel 
shows that trusty drivers are in use... see below ..


    >>>>> Are trusty drivers for Intel GM965 graphics chip broken ? <<<<<

o Both these links suggest  
http://forums.debian.net/viewtopic.php?f=5&t=49881
https://github.com/ValveSoftware/steam-for-linux/issues/3466
installing 
libgl1mesa-dri (Direct Rendering interface)
for the GM965 graphics chip.
I installed
 libgl1-mesa-dri 
in the synaptic package manager, though both this and libgl1-mesa-glx now appear greyed out with an exclamation mark in the check box  synaptic (post install)

Thank you

:)

Jas


System:    Kernel: 3.13.0-37-generic i686 (32 bit, gcc: 4.8.2) 
Desktop: Gnome Distro: Linux Mint 17.1 Rebecca
Machine:   System: LENOVO (portable) product: 7661CH8 version: ThinkPad T61
Mobo: LENOVO model: 7661CH8 Bios: LENOVO version: 7LET44WW (1.14 ) date: 06/27/2007
CPU:       Dual core Intel Core2 Duo CPU T7100 (-MCP-) cache: 2048 KB flags: (lm nx sse sse2 sse3 ssse3 vmx) bmips: 7181.94 
           Clock Speeds: 1: 800.00 MHz 2: 800.00 MHz
Graphics:  Card: Intel Mobile GM965/GL960 Integrated Graphics Controller (primary) bus-ID: 00:02.0 
           X.Org: 1.15.1 drivers: intel (unloaded: fbdev,vesa) Resolution: 1440x900@60.1hz 
           GLX Renderer: Mesa DRI Intel 965GM x86/MMX/SSE2 GLX Version: 2.1 Mesa 10.1.3 Direct Rendering: Yes
Audio:     Card: Intel 82801H (ICH8 Family) HD Audio Controller driver: snd_hda_intel bus-ID: 00:1b.0
           Sound: Advanced Linux Sound Architecture ver: k3.13.0-37-generic
Network:   Card-1: Intel 82566MM Gigabit Network Connection driver: e1000e ver: 2.3.2-k port: 1840 bus-ID: 00:19.0
           IF: eth0 state: down mac: <filter>
           Card-2: Intel PRO/Wireless 3945ABG [Golan] Network Connection driver: iwl3945 ver: in-tree:s bus-ID: 03:00.0
           IF: wlan0 state: up mac: <filter>
Drives:    HDD Total Size: 240.1GB (3.5% used) 1: id: /dev/sda model: KINGSTON_SV300S3 size: 240.1GB 
Partition: ID: / size: 219G used: 8.0G (4%) fs: ext4 ID: swap-1 size: 2.10GB used: 0.25GB (12%) fs: swap 
RAID:      No RAID devices detected - /proc/mdstat and md_mod kernel raid module present
Sensors:   System Temperatures: cpu: 58.0C mobo: 34.0C 
           Fan Speeds (in rpm): cpu: 0 
Info:      Processes: 179 Uptime: 1 day Memory: 1331.2/1975.0MB Runlevel: 2 Gcc sys: 4.8.2 Client: Shell inxi: 1.8.4


$ apt-cache policy xserver-xorg-video-intel
xserver-xorg-video-intel:
  Installed: 2:2.99.910-0ubuntu1.1
  Candidate: 2:2.99.910-0ubuntu1.3
  Version table:
     2:2.99.910-0ubuntu1.3 0
        500 http://archive.ubuntu.com/ubuntu/ trusty-updates/main i386 Packages
 *** 2:2.99.910-0ubuntu1.1 0
        100 /var/lib/dpkg/status
     2:2.99.910-0ubuntu1 0
        500 http://archive.ubuntu.com/ubuntu/ trusty/main i386 Packages

>>>>> Are trusty drivers broken ? <<<<<


$ glxgears
Running synchronized to the vertical refresh.  The framerate should be
approximately the same as the monitor refresh rate.
301 frames in 5.0 seconds = 60.024 FPS
300 frames in 5.0 seconds = 59.884 FPS
305 frames in 5.0 seconds = 60.915 FPS
300 frames in 5.0 seconds = 59.994 FPS
301 frames in 5.0 seconds = 60.000 FPS
301 frames in 5.0 seconds = 60.005 FPS
301 frames in 5.0 seconds = 60.000 FPS


 $ glxinfo
name of display: :0
display: :0  screen: 0
direct rendering: Yes
server glx vendor string: SGI
server glx version string: 1.4
server glx extensions:
    GLX_ARB_create_context, GLX_ARB_create_context_profile, 
    GLX_ARB_fbconfig_float, GLX_ARB_framebuffer_sRGB, GLX_ARB_multisample, 
    GLX_EXT_create_context_es2_profile, GLX_EXT_framebuffer_sRGB, 
    GLX_EXT_import_context, GLX_EXT_texture_from_pixmap, GLX_EXT_visual_info, 
    GLX_EXT_visual_rating, GLX_INTEL_swap_event, GLX_MESA_copy_sub_buffer, 
    GLX_OML_swap_method, GLX_SGIS_multisample, GLX_SGIX_fbconfig, 
    GLX_SGIX_pbuffer, GLX_SGIX_visual_select_group, GLX_SGI_swap_control
client glx vendor string: Mesa Project and SGI
client glx version string: 1.4
client glx extensions:
    GLX_ARB_create_context, GLX_ARB_create_context_profile, 
    GLX_ARB_create_context_robustness, GLX_ARB_fbconfig_float, 
    GLX_ARB_framebuffer_sRGB, GLX_ARB_get_proc_address, GLX_ARB_multisample, 
    GLX_EXT_create_context_es2_profile, GLX_EXT_fbconfig_packed_float, 
    GLX_EXT_framebuffer_sRGB, GLX_EXT_import_context, 
    GLX_EXT_texture_from_pixmap, GLX_EXT_visual_info, GLX_EXT_visual_rating, 
    GLX_INTEL_swap_event, GLX_MESA_copy_sub_buffer, 
    GLX_MESA_multithread_makecurrent, GLX_MESA_query_renderer, 
    GLX_MESA_swap_control, GLX_OML_swap_method, GLX_OML_sync_control, 
    GLX_SGIS_multisample, GLX_SGIX_fbconfig, GLX_SGIX_pbuffer, 
    GLX_SGIX_visual_select_group, GLX_SGI_make_current_read, 
    GLX_SGI_swap_control, GLX_SGI_video_sync
GLX version: 1.4
GLX extensions:
    GLX_ARB_create_context, GLX_ARB_create_context_profile, 
    GLX_ARB_fbconfig_float, GLX_ARB_framebuffer_sRGB, 
    GLX_ARB_get_proc_address, GLX_ARB_multisample, 
    GLX_EXT_create_context_es2_profile, GLX_EXT_framebuffer_sRGB, 
    GLX_EXT_import_context, GLX_EXT_texture_from_pixmap, GLX_EXT_visual_info, 
    GLX_EXT_visual_rating, GLX_INTEL_swap_event, GLX_MESA_copy_sub_buffer, 
    GLX_MESA_multithread_makecurrent, GLX_MESA_query_renderer, 
    GLX_MESA_swap_control, GLX_OML_swap_method, GLX_OML_sync_control, 
    GLX_SGIS_multisample, GLX_SGIX_fbconfig, GLX_SGIX_pbuffer, 
    GLX_SGIX_visual_select_group, GLX_SGI_make_current_read, 
    GLX_SGI_swap_control, GLX_SGI_video_sync
OpenGL vendor string: Intel Open Source Technology Center
OpenGL renderer string: Mesa DRI Intel(R) 965GM x86/MMX/SSE2
OpenGL version string: 2.1 Mesa 10.1.3
OpenGL shading language version string: 1.20
OpenGL extensions:
    GL_3DFX_texture_compression_FXT1, GL_AMD_seamless_cubemap_per_texture, 
    GL_AMD_shader_trinary_minmax, GL_ANGLE_texture_compression_dxt3, 
    GL_ANGLE_texture_compression_dxt5, GL_APPLE_object_purgeable, 
    GL_APPLE_packed_pixels, GL_APPLE_vertex_array_object, 
    GL_ARB_ES2_compatibility, GL_ARB_clear_buffer_object, 
    GL_ARB_color_buffer_float, GL_ARB_copy_buffer, GL_ARB_debug_output, 
    GL_ARB_depth_buffer_float, GL_ARB_depth_clamp, GL_ARB_depth_texture, 
    GL_ARB_draw_buffers, GL_ARB_draw_elements_base_vertex, 
    GL_ARB_draw_instanced, GL_ARB_explicit_attrib_location, 
    GL_ARB_fragment_coord_conventions, GL_ARB_fragment_program, 
    GL_ARB_fragment_program_shadow, GL_ARB_fragment_shader, 
    GL_ARB_framebuffer_object, GL_ARB_framebuffer_sRGB, 
    GL_ARB_get_program_binary, GL_ARB_half_float_pixel, 
    GL_ARB_half_float_vertex, GL_ARB_instanced_arrays, 
    GL_ARB_internalformat_query, GL_ARB_invalidate_subdata, 
    GL_ARB_map_buffer_alignment, GL_ARB_map_buffer_range, GL_ARB_multisample, 
    GL_ARB_multitexture, GL_ARB_occlusion_query, GL_ARB_occlusion_query2, 
    GL_ARB_pixel_buffer_object, GL_ARB_point_parameters, GL_ARB_point_sprite, 
    GL_ARB_provoking_vertex, GL_ARB_robustness, GL_ARB_sampler_objects, 
    GL_ARB_seamless_cube_map, GL_ARB_shader_bit_encoding, 
    GL_ARB_shader_objects, GL_ARB_shader_texture_lod, 
    GL_ARB_shading_language_100, GL_ARB_shadow, GL_ARB_sync, 
    GL_ARB_texture_border_clamp, GL_ARB_texture_compression, 
    GL_ARB_texture_compression_rgtc, GL_ARB_texture_cube_map, 
    GL_ARB_texture_env_add, GL_ARB_texture_env_combine, 
    GL_ARB_texture_env_crossbar, GL_ARB_texture_env_dot3, 
    GL_ARB_texture_float, GL_ARB_texture_mirror_clamp_to_edge, 
    GL_ARB_texture_mirrored_repeat, GL_ARB_texture_non_power_of_two, 
    GL_ARB_texture_rectangle, GL_ARB_texture_rg, GL_ARB_texture_rgb10_a2ui, 
    GL_ARB_texture_storage, GL_ARB_texture_swizzle, GL_ARB_transpose_matrix, 
    GL_ARB_vertex_array_bgra, GL_ARB_vertex_array_object, 
    GL_ARB_vertex_attrib_binding, GL_ARB_vertex_buffer_object, 
    GL_ARB_vertex_program, GL_ARB_vertex_shader, 
    GL_ARB_vertex_type_2_10_10_10_rev, GL_ARB_window_pos, 
    GL_ATI_blend_equation_separate, GL_ATI_draw_buffers, 
    GL_ATI_envmap_bumpmap, GL_ATI_separate_stencil, 
    GL_ATI_texture_env_combine3, GL_ATI_texture_float, GL_EXT_abgr, 
    GL_EXT_bgra, GL_EXT_blend_color, GL_EXT_blend_equation_separate, 
    GL_EXT_blend_func_separate, GL_EXT_blend_minmax, GL_EXT_blend_subtract, 
    GL_EXT_compiled_vertex_array, GL_EXT_copy_texture, GL_EXT_draw_buffers2, 
    GL_EXT_draw_instanced, GL_EXT_draw_range_elements, GL_EXT_fog_coord, 
    GL_EXT_framebuffer_blit, GL_EXT_framebuffer_object, 
    GL_EXT_framebuffer_sRGB, GL_EXT_gpu_program_parameters, 
    GL_EXT_multi_draw_arrays, GL_EXT_packed_depth_stencil, 
    GL_EXT_packed_float, GL_EXT_packed_pixels, GL_EXT_pixel_buffer_object, 
    GL_EXT_point_parameters, GL_EXT_polygon_offset, GL_EXT_provoking_vertex, 
    GL_EXT_rescale_normal, GL_EXT_secondary_color, 
    GL_EXT_separate_shader_objects, GL_EXT_separate_specular_color, 
    GL_EXT_shadow_funcs, GL_EXT_stencil_two_side, GL_EXT_stencil_wrap, 
    GL_EXT_subtexture, GL_EXT_texture, GL_EXT_texture3D, 
    GL_EXT_texture_array, GL_EXT_texture_compression_dxt1, 
    GL_EXT_texture_compression_rgtc, GL_EXT_texture_compression_s3tc, 
    GL_EXT_texture_cube_map, GL_EXT_texture_edge_clamp, 
    GL_EXT_texture_env_add, GL_EXT_texture_env_combine, 
    GL_EXT_texture_env_dot3, GL_EXT_texture_filter_anisotropic, 
    GL_EXT_texture_integer, GL_EXT_texture_lod_bias, GL_EXT_texture_object, 
    GL_EXT_texture_rectangle, GL_EXT_texture_sRGB, GL_EXT_texture_sRGB_decode, 
    GL_EXT_texture_shared_exponent, GL_EXT_texture_snorm, 
    GL_EXT_texture_swizzle, GL_EXT_vertex_array, GL_EXT_vertex_array_bgra, 
    GL_IBM_multimode_draw_arrays, GL_IBM_rasterpos_clip, 
    GL_IBM_texture_mirrored_repeat, GL_INGR_blend_func_separate, GL_KHR_debug, 
    GL_MESA_pack_invert, GL_MESA_texture_signed_rgba, GL_MESA_window_pos, 
    GL_NV_blend_square, GL_NV_conditional_render, GL_NV_depth_clamp, 
    GL_NV_light_max_exponent, GL_NV_packed_depth_stencil, 
    GL_NV_primitive_restart, GL_NV_texgen_reflection, 
    GL_NV_texture_env_combine4, GL_NV_texture_rectangle, GL_OES_EGL_image, 
    GL_OES_read_format, GL_S3_s3tc, GL_SGIS_generate_mipmap, 
    GL_SGIS_texture_border_clamp, GL_SGIS_texture_edge_clamp, 
    GL_SGIS_texture_lod, GL_SUN_multi_draw_arrays

12 GLX Visuals
    visual  x   bf lv rg d st  colorbuffer  sr ax dp st accumbuffer  ms  cav
  id dep cl sp  sz l  ci b ro  r  g  b  a F gb bf th cl  r  g  b  a ns b eat
----------------------------------------------------------------------------
0x020 24 tc  0  32  0 r  y .   8  8  8  8 .  .  0 24  8  0  0  0  0  0 0 None
0x021 24 dc  0  32  0 r  y .   8  8  8  8 .  .  0 24  8  0  0  0  0  0 0 None
0x075 24 tc  0  32  0 r  y .   8  8  8  8 .  .  0  0  0  0  0  0  0  0 0 None
0x076 24 tc  0  32  0 r  . .   8  8  8  8 .  .  0  0  0  0  0  0  0  0 0 None
0x077 24 tc  0  32  0 r  . .   8  8  8  8 .  .  0 24  8  0  0  0  0  0 0 None
0x078 24 tc  0  32  0 r  y .   8  8  8  8 .  .  0 24  8 16 16 16 16  0 0 Slow
0x079 24 dc  0  32  0 r  y .   8  8  8  8 .  .  0  0  0  0  0  0  0  0 0 None
0x07a 24 dc  0  32  0 r  . .   8  8  8  8 .  .  0  0  0  0  0  0  0  0 0 None
0x07b 24 dc  0  32  0 r  . .   8  8  8  8 .  .  0 24  8  0  0  0  0  0 0 None
0x07c 24 dc  0  32  0 r  y .   8  8  8  8 .  .  0 24  8  0  0  0  0  0 0 None
0x07d 24 dc  0  32  0 r  y .   8  8  8  8 .  .  0 24  8 16 16 16 16  0 0 Slow
0x05c 32 tc  0  32  0 r  y .   8  8  8  8 .  .  0 24  8  0  0  0  0  0 0 None

24 GLXFBConfigs:
    visual  x   bf lv rg d st  colorbuffer  sr ax dp st accumbuffer  ms  cav
  id dep cl sp  sz l  ci b ro  r  g  b  a F gb bf th cl  r  g  b  a ns b eat
----------------------------------------------------------------------------
0x05d  0 tc  0  16  0 r  y .   5  6  5  0 .  .  0  0  0  0  0  0  0  0 0 None
0x05e  0 tc  0  16  0 r  . .   5  6  5  0 .  .  0  0  0  0  0  0  0  0 0 None
0x05f  0 tc  0  16  0 r  y .   5  6  5  0 .  .  0 16  0  0  0  0  0  0 0 None
0x060  0 tc  0  16  0 r  . .   5  6  5  0 .  .  0 16  0  0  0  0  0  0 0 None
0x061 24 tc  0  32  0 r  y .   8  8  8  8 .  .  0  0  0  0  0  0  0  0 0 None
0x062 24 tc  0  32  0 r  . .   8  8  8  8 .  .  0  0  0  0  0  0  0  0 0 None
0x063 24 tc  0  32  0 r  y .   8  8  8  8 .  .  0 24  8  0  0  0  0  0 0 None
0x064 24 tc  0  32  0 r  . .   8  8  8  8 .  .  0 24  8  0  0  0  0  0 0 None
0x065  0 tc  0  16  0 r  y .   5  6  5  0 .  .  0 16  0  0  0  0  0  0 0 None
0x066  0 tc  0  16  0 r  y .   5  6  5  0 .  .  0 16  0 16 16 16  0  0 0 Slow
0x067 32 tc  0  32  0 r  y .   8  8  8  8 .  .  0 24  8  0  0  0  0  0 0 None
0x068 24 tc  0  32  0 r  y .   8  8  8  8 .  .  0 24  8 16 16 16 16  0 0 Slow
0x069  0 dc  0  16  0 r  y .   5  6  5  0 .  .  0  0  0  0  0  0  0  0 0 None
0x06a  0 dc  0  16  0 r  . .   5  6  5  0 .  .  0  0  0  0  0  0  0  0 0 None
0x06b  0 dc  0  16  0 r  y .   5  6  5  0 .  .  0 16  0  0  0  0  0  0 0 None
0x06c  0 dc  0  16  0 r  . .   5  6  5  0 .  .  0 16  0  0  0  0  0  0 0 None
0x06d 24 dc  0  32  0 r  y .   8  8  8  8 .  .  0  0  0  0  0  0  0  0 0 None
0x06e 24 dc  0  32  0 r  . .   8  8  8  8 .  .  0  0  0  0  0  0  0  0 0 None
0x06f 24 dc  0  32  0 r  y .   8  8  8  8 .  .  0 24  8  0  0  0  0  0 0 None
0x070 24 dc  0  32  0 r  . .   8  8  8  8 .  .  0 24  8  0  0  0  0  0 0 None
0x071  0 dc  0  16  0 r  y .   5  6  5  0 .  .  0 16  0  0  0  0  0  0 0 None
0x072  0 dc  0  16  0 r  y .   5  6  5  0 .  .  0 16  0 16 16 16  0  0 0 Slow
0x073 24 dc  0  32  0 r  y .   8  8  8  8 .  .  0 24  8  0  0  0  0  0 0 None
0x074 24 dc  0  32  0 r  y .   8  8  8  8 .  .  0 24  8 16 16 16 16  0 0 Slow