I use page flipping. The frame indicator (simple palette switching for color 0) indicates a refresh time of about 1/8 frame.

Problem : my game skip one frame every 10 or 15 seconds, or more depending on what is running in the background in Windows. I think the reason is that a vsync is not detected because my program is not active at that particular moment.

How can I give a higher priority to my game, or make sure that it will be active when the vsync occurs ?

Any help appreciated !!