Frames per Second..

Yep.
In windowed mode, the two buffers are being copied, byte by byte. This happens as fast as the CPU / GPU can do it, although you''ll only actually see 60 of those frames (if your monitor is at 60Hz), because the monitor cant refresh that fast.
In fullscreen, the two buffers are page flipped (unless you specify otherwise). This causes the screen to be updated at the speed of the monitor (60Hz or 60FPS).
When you add more detail to your scene, and get < 60 FPS, you''ll see that the program runs faster in fullscreen mode because of the page flipping (two pointers [4-byte values] being exchanged instead of thousands for every pixel).

HTH, Steve

Steve
DirectX Programmer
Soon to be the new Bill Gates

Well I fixed it myself. after reading the SDK doc I found out that in fullscreen, your Frames Per Second can''t go higher than your Monitor refreshrate

But you can make it do by filling the D3D Parameter:

d3dpp.FullScreen_PresentationInterval = D3DPRESENT_INTERVAL_IMMEDIATE;

see also http://www.gamedev.net/community/forums/topic.asp?topic_id=102305

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