It is certainly peculiar that you just see a blank screen. According to the
specs for your video card you should have no problem running GZDoom.
Try running GZDoom from the command line
gzdoom.exe +logfile startup.txt
which will create a file startup.txt. Then look through it to check for something that seems amiss.
You should get something like this:
[spoiler]Log started: Mon Jun 30 21:32:13 2008
W_Init: Init WADfiles.
adding K:/DOOM/GZDoomR129/gzdoom.pk3
adding K:/DOOM/IWADS/doom2.wad (2919 lumps)
adding K:/DOOM/GZDoomR129/skins/lights.wad (4 lumps)
I_Init: Setting up machine state.
CPU Speed: 2210.100850 MHz
CPU Vendor ID: AuthenticAMD
Name: AMD Athlon(tm) 64 X2 Dual Core Processor 4200+
Family 15 (15), Model 43, Stepping 1
Features: MMX MMX+ SSE SSE2 SSE3 3DNow! 3DNow!+
I_InitSound: Initializing FMOD
FMOD Sound System, copyright © Firelight Technologies Pty, Ltd., 1994-2008.
V_Init: allocate screen.
S_Init: Setting up sound.
ST_Init: Init startup screen.
P_Init: Checking cmd-line parameters...
G_ParseMapInfo: Load map definitions.
S_InitData: Load sound definitions.
TEAMINFO_Init: Load team definitions.
LoadDecorations: Load external actors.
R_Init: Init Doom refresh subsystem.
DecalLibrary: Load decals.
M_Init: Init miscellaneous info.
P_Init: Init Playloop state.
ParseSBarInfo: Loading custom status bar definition.
D_CheckNetGame: Checking network game status.
player 1 of 1 (1 nodes)
I_InitInput
I_StartupMouse
I_StartupJoystick
I_StartupKeyboard
GL_VENDOR: NVIDIA Corporation
GL_RENDERER: GeForce 7800 GT/PCI/SSE2
GL_VERSION: 2.0.3
GL_EXTENSIONS: GL_ARB_color_buffer_float GL_ARB_depth_texture GL_ARB_draw_buffers GL_ARB_fragment_program GL_ARB_fragment_program_shadow GL_ARB_fragment_shader GL_ARB_half_float_pixel GL_ARB_imaging GL_ARB_multisample GL_ARB_multitexture GL_ARB_occlusion_query GL_ARB_pixel_buffer_object GL_ARB_point_parameters GL_ARB_point_sprite GL_ARB_shadow GL_ARB_shader_objects GL_ARB_shading_language_100 GL_ARB_texture_border_clamp GL_ARB_texture_compression GL_ARB_texture_cube_map GL_ARB_texture_env_add GL_ARB_texture_env_combine GL_ARB_texture_env_dot3 GL_ARB_texture_float GL_ARB_texture_mirrored_repeat GL_ARB_texture_non_power_of_two GL_ARB_texture_rectangle GL_ARB_transpose_matrix GL_ARB_vertex_buffer_object GL_ARB_vertex_program GL_ARB_vertex_shader GL_ARB_window_pos GL_ATI_draw_buffers GL_ATI_texture_float GL_ATI_texture_mirror_once GL_S3_s3tc GL_EXT_texture_env_add 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_Cg_shader GL_EXT_depth_bounds_test GL_EXT_draw_range_elements GL_EXT_fog_coord GL_EXT_framebuffer_object GL_EXT_multi_draw_arrays GL_EXT_packed_depth_stencil GL_EXT_packed_pixels GL_EXT_pixel_buffer_object GL_EXT_point_parameters GL_EXT_rescale_normal GL_EXT_secondary_color GL_EXT_separate_specular_color GL_EXT_shadow_funcs GL_EXT_stencil_two_side GL_EXT_stencil_wrap GL_EXT_texture3D GL_EXT_texture_compression_s3tc GL_EXT_texture_cube_map GL_EXT_texture_edge_clamp GL_EXT_texture_env_combine GL_EXT_texture_env_dot3 GL_EXT_texture_filter_anisotropic GL_EXT_texture_lod GL_EXT_texture_lod_bias GL_EXT_texture_mirror_clamp GL_EXT_texture_object GL_EXT_texture_sRGB GL_EXT_timer_query GL_EXT_vertex_array GL_IBM_rasterpos_clip GL_IBM_texture_mirrored_repeat GL_KTX_buffer_region GL_NV_blend_square GL_NV_copy_depth_to_color GL_NV_depth_clamp GL_NV_fence GL_NV_float_buffer GL_NV_fog_distance GL_NV_fragment_program GL_NV_fragment_program_option GL_NV_fragment_program2 GL_NV_half_float GL_NV_light_max_exponent GL_NV_multisample_filter_hint GL_NV_occlusion_query GL_NV_packed_depth_stencil GL_NV_pixel_data_range GL_NV_point_sprite GL_NV_primitive_restart GL_NV_register_combiners GL_NV_register_combiners2 GL_NV_texgen_reflection GL_NV_texture_compression_vtc GL_NV_texture_env_combine4 GL_NV_texture_expand_normal GL_NV_texture_rectangle GL_NV_texture_shader GL_NV_texture_shader2 GL_NV_texture_shader3 GL_NV_vertex_array_range GL_NV_vertex_array_range2 GL_NV_vertex_program GL_NV_vertex_program1_1 GL_NV_vertex_program2 GL_NV_vertex_program2_option GL_NV_vertex_program3 GL_NVX_conditional_render GL_SGIS_generate_mipmap GL_SGIS_texture_lod GL_SGIX_depth_texture GL_SGIX_shadow GL_SUN_slice_accum GL_WIN_swap_hint WGL_EXT_swap_control
Support for non power 2 textures enabled.
Occlusion query enabled.
Resolution: 1680 x 1050
MAP01 - entryway[/spoiler]
Other than that, look through the
zdoom-xxyyzz.ini file for something odd.
Possibly, your iwad file could be corrupted.
Try version R129M from
Nash's site.