Windows 7: Warhammer Online issue

Hey,

(Computer description)
Windows 7 Ultimate 7600 RTM (x84)
8800GTS Nvidia gfx card (Windows 7 Drivers)
AMD Athlon x64 X2 5600+ 2.6ghz
4ghz Kingston HyperX Ram

(Problem Description)
I have just upgraded to Windows7, from Windows XP SP2 (which warhammer ran on) I can start the game fine, once it gets to the character selection screen NORMALLY runs fine, then about 1-5 minutes into the game it stops, (No error) the screen usually loses some models, like a building will dissapear and holes appear in my character and the graphics go nutty. Then about 4-6 seconds after that my monitor turns off, goes into sleep mode, then comes back on, goes off etc. Unsure if sound continues during this time. I have to force a restart to get my computer running again. Sometimes this doesn't happen for more than 5 minutes and I can run around not doing anything exciting.

I'm almost 100% sure all my drivers etc are windows7 compatible.

Also the warhammer is a drag from my old windows files. I just click dragged it into my new program files. I would reinstall it but my CD drive doesn't like windows. Currently trying to fix that problem also so I can do a fresh proper install of Warhammer.

Thanks for any help in advance.
Andrew