My Mac won't sleep

I have a 8 Core Mac Pro and it won't go to sleep. I have non OSX compliant PCIe cards in there (for Windows) do you guys think that's the reason???

 

What it does on mine is it kind of shuts down, then I hear the ATI fan, then comes back to OSX? Do you get the same?

What does Last.FM mean?

 

I took it out and it seems to be culprit.

In the manual for this Windows based card, it does state that the device does not support "sleep mode". That's understandable, but under OSX it is not even recognized, so why is OSX being limited by the cards function?

Any clues guys? I think I'm the only one that uses a Windows only card in his Mac hehe

Just checked, and not much is running besides the usual default applications. It slept without the card in the system...actually it's a set of 2 PCIe cards, so....

 

What I meant by that was since OSX does not recognize it, why won't it sleep when I go to sleep from OSX?

I don't expect these cards to work under OSX, just sleep at least....but it seems to be a hardware issue that's preventing the computer from going to sleep.