9800GT Black Screen Only With Win7/Vista X65 Drivers

I got a Asus P5Q-E Mobo, 8gb ram

Having Windows 7 7077 x64 installed for one week and before the upgrade nearly 2 months with build 7000.

I bought a new gpu, and replaces my old 8500GTS with a new 9800GT,

Problem is, Windows find the gpu, installs standard driver. all fine.

Second, Install new Win beta 7 Drivers (was trying new vista x64 drivers too), and i got black screen and lockup half time in install progress and when doing a hard restart right before Loginscreen also.

Restart, and windows is doing reset, and old drivers back.

Trying to install several times. no luck with any settings or admin settings to install, same problem, black restart black reset, black restart black reset, black restart black reset.... etc etc.

Putting back the old gpu, install same drivers, power of, putt new gpu in, and its getting black...

What is the problem? I cant find any info in systemlogg either, but the gpu works with standard drivers from windows

I hope i havent missed anything

Edit: My psu is Corsair 650w, i got 10 HDs, and it uses max 220-260w what i have tested, a bit more while playing (old gpu)

I will get a Vertex SSD this week, maybe the problems solves when installing a fresh Windows 7 on it? Otherwise i hope someone knows the issue.

Edit2:

Updated Bios on Mobo, Adaptec 2405 and Rocketraid 2320, Still same issue.

I have noticed that the HD led blinks all the time with that gpu, and its gets very hot...

I plugged out the power of my 2x5hds hotswapmodule, so only one hd was active and same error accured, The problems dissapears when i but pack the old gpu.