I have a very simple line drawing single threaded app which ran very fast on Intel 865 MB integrated graphics... But it runs slow on Geforce 6200 external Graphics card Its totally crazy !! Has anyone had such a problem ?

Most of the perceived "slow" issues come from driver specific issues. Check to make sure you have the latest drivers installed on your Geforce (or if you do have the latest, that may be the problem) Make sure you check against Vertical sync options, Antialasing, etc... to make sure the card is not set on high quality which would give a lower performance than a profile of high performance.

Other factors include the computer itself, other background processes running, and most of the time the code you are trying to execute. Double check to make sure it does not already make sense that one computer should operate better than another [wink]

Thank you very much Hodgman & Drew_Benton
Talking about fps....

Its a CAD application, so there is no continuous render loop here.

I draw only when necessary... (i.e. on each mouse move event) for drawing snap points, live preview (while moving mouse to pick 2nd point for a line)

Is it necessary to calculate the fps here?

The difference I feel is When I move the mouse for drawing a circle for example, when I was using Intel 865 integrated graphics, I didn't feel that the graphics update were slower than the mouse movement, wherever my mouse goes, the circle was updated very fast that you wont feel anything slow (like in ms paint circle tool)

but here in GF 6200, I can see the circle graphics running behind the mouse. The graphics update is slower. when i move my mouse from one corner of my window to another, the graphics slowly flow on the same path as the mouse move.

same happens when i move the shape. like in a pick and place operation, the graphics goes slowly behind the mouse...

This application just uses primitives, not lighting, texturing etc.

I downloaded latest drivers both from guru3d(beta) and nvidia official latest ones. No changes on both. I think its some opengl initialization settings problem.

i tested on a Latest Intel 965 with X3000 GMA, then with the Geforce 6200 on it.
same results.

Onboard X3000 GMA gives performance similar to 865 integrated graphics...

No other configuration changes.

Still no light on this ???