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mr5zzz
01-08-2014, 06:37 PM
I have recently tried the use of VBO. I just copy pasted the code from this site(This site preventing me to post the URL) ("")

It compiles fine and seems running well. However, I noticed on the taskmanager that the program runs at 50% CPU usage. Its just a simple triangle, nothing else. I was expecting it to be of 0% because all of other programs I created in glfw3 runs on 0% when idle. I know that V-SYNC in glfw3 is set true by default, but still I add this line of code to ensure
glfwSetInterval(GL_TRUE); //sets V-SYNC on but still nothings changed.

After messing with the `test_vs.glsl` (I think this has nothing to do with the problem):

code I changed:

from


in vec3 vp;

void main ()
{
gl_Position = vec4 (vp, 1.0);
}

to


in vec2 vp;

void main ()
{
gl_Position = vec4 (vp, 0, 1.0);
}

And changed attributes of vertex in .cpp code to 2D.

Running several times the `Hello Triangle` program again, computer stops and hang a bit ---> Then **CRAASSH**. The graphics card is broken! (literally ouch). The computer shutdowns itself, and I try rebooting it again, I got a screen with full of random lines displaying and fail to continue on desktop.

I don't have much of the information about the graphics card but glew says
GeForce 7300 GT/PCI/SSE2/3DNOW! and running on Windows XP with OpenGL v2.1 support according to glew.

Some of the extensions I added:



glfwWindowHint(GLFW_SAMPLES, 4);

glfwWindowHint(GLFW_OPENGL_CORE_PROFILE, 2);

glewExperimental = GL_TRUE;
And I add the prefix ARB to any function related to VBO



I suspect this is due to lack of OpenGL extensions support check. But, is that so really the problem? Is it the simple program or other? If so, why would they let this to happen?

Dark Photon
01-09-2014, 06:10 AM
That is very unusual. No OpenGL code you can write for your GPU should be able to permanently crash your computer unless your computer/GPU is insufficiently powered and cooled, or the hardware is flaky. If it isn't, then of course you can do hardware damage. But this isn't a fault of OpenGL or an OpenGL driver. It's the fault of the person that built your system, or just due to the hardware getting old.

Case-in-point. If your GPU has a fan, and over the many years the fan gets wedged up (dust, bearings fail,
etc.), you're system's ready for a crash. GeForce 7 is pretty darn old at this point.

(Also, don't cross post -- that is, don't post multiple copies of the same message to different boards on this forum. I deleted your other post.)

mhagain
01-09-2014, 01:05 PM
50% CPU in Task Manager, by the way, indicates that (1) you've got a dual-core CPU, and (2) you're using some form of busy-waiting (http://en.wikipedia.org/wiki/Busy_waiting) in your main loop (you may not even be explicitly doing this; your driver may be the one that's at fault here). Busy-waiting will chew up CPU usage like this even if it seems to be doing nothing (or not much).

mr5zzz
03-01-2014, 07:30 AM
It has been done already, I cannot do anything about it, anyway, I got a new GC again, same as the old one that have crashed. Now I feared to do GLSL again.

andrytim0er
03-02-2014, 06:12 PM
Running several times the `Hello Triangle` program again, computer stops and hang a bit ---> Then **CRAASSH**. The graphics card is broken! (literally ouch). The computer shutdowns itself, and I try rebooting it again, I got a screen with full of random lines displaying and fail to continue on desktop.