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04-12-2002, 04:39 AM
Hello,

I have an Asus V8200 Deluxe GF3 w/ 64MB memory. I am running a simple model of about 30k triangles. My FPS seems to match my monitor refresh rate. If I set it at 60 Hz I get 60 FPS and if I go up tp 75 I get that many FPS. First that seems odd and second that seems slow for the model I have. (No lighting, texturing, or what ever. Just a vertex array and RGB colors).

I installed nVidia's new drivers but that did not change a darn thing. (before I was susing Asus' drivers).

I am compiling and linking using MS VC++ and cygwin on a W2K box. Do i have to link against any special libraries that allow for hardware acceleration?


Your help is greatly appreciated.

Regards,
Frustrated with OpenGL under W2K

Furrage
04-12-2002, 05:58 AM
Sounds like you have vertical sync enabled. I don't know much about controlling it (yet http://www.opengl.org/discussion_boards/ubb/smile.gif ) but do a search in the forum for the last month for "Vertical Sync" and "vsync", and you should get the answers.

04-12-2002, 12:31 PM
You can set the screen mode/refresh rate via windows calls.

As the dude above said, if you have vsync on, then fps is tied to that. You can get powerstrip or another util, or even the control panel to turn vsync off if you want.

Why does it seem odd? 60Hz= 60 updates per sec, same goes for 75. For 30K tris, it really depends how you are rendering them, and the size, and culling, and all that good mojo. Your CPU also plays a factor in this.

Jack
04-13-2002, 02:02 AM
One more possibility...

I'm not sure about W2k, but on XP Microsoft have capped the maximum allowable refresh on OpenGL to 60fps and DirectX to 75fps, perhaps they did a similar thing on W2k... If so, there is a program that's supposed to fix it...can't remember URL, but if the other idea's don't work it may be worth looking up...

mproso
04-13-2002, 05:29 AM
Usually vsync can be turn on and off in driver properties but
you can control vsync in youre program with WGL_EXT_swap_control extension and
you can change refresh rate with Win32 API function ChangeDisplaySettings.

Regards,
mproso

Michael Steinberg
04-13-2002, 06:11 AM
AFAIK windows XP doesnt cap the fps at 60 fps or refreshes per second. Its just that 60 hz is the default refresh rate when the programmer didnt specify another refresh rate and switched the desktop settings, as many do.