Fullscreen possible in Windows Vista?

Well I've always had it on Fullscreen. I can't say why I can and you can't because it's always been like that, but it can happen.

hmmm if you get it to start but some widow contents wrong , do driver upgrades, and turn on the aa on video card, it worked for me

I too have a 9800 GTX, however, I usually play windowed. Because for some strange reason on Vista, playing full screen = massive lag if I have more than a few ships/planets in a system. My FPS drops from 40 to like 10-15, which is ridiculous considering I have a computer that can play CoD4 and Supreme Commander on max settings with no lag.

The reason is not strange at all; SE5 uses DX 8.1, which has to be emulated in Vista's DX10 engine.

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Is there a way to increase performance in full screen? I trid changing to use my 9800GTX but, as others have found, can only run in a window.
Using the default, I'm only getting 30fps!!!!
I get higher than that in far more demanding games.

Q6600, Rampage Formula Mobo, 2Gb Ram, X-fi Prelude.