GeForce 6600 GT AGP problem..maybe with my motherboard?

Greetings,
I just bought the video card stated in the thread title. It was tested at the shop in front of my eyes so I'm sure it works perfectly.
But, something with my pc is wrong with this card: when I power up the pc, the monitor remains black and nothing happens. Of course, with my old video card (Radeon 9800 pro) everything worked fine. I correctly unistalled any ATI driver and program from my pc (using the ATI Cat Uninstaller) before proceeding with the GeForce.
Here is my pc:

450 W power source
Azza KT400-ANB motherboard, with Via KT400 chip, 8x AGP, FSB 333mhz, ATA 133
Athlon XP 2400+ CPU
512 mb ddr ram
2 ide HD (80 GB / 30 GB)
cd-rom w/rw
dvd-rom reader & cd w/rw
Creative Sound Blaster Live! sound card
Video card as stated before
MS Windows XP Professional + SP 1

I asked to the shop tech support and they told me it could be:

- Insufficient power for all the hardware, since the GT6600 requires more power than the 9800pro. I doubt it since 450W seems good to me, and anyway I tried connecting just the primary hard disk and the GeForce, and the result was the same.

- Compatibility problems between the Azza motherboard and the GeForce. I tried installing the latest VIA drivers (from www.viaarena.com, since the Azza site is down..sigh): Hyperion 4 in 1 v456v. I didn't tried to shut down and install the GeForce yet, but I'll do it after posting this thread.

Do you have any advice? I have no idea about what to do except upading the MB drivers...I'm seriously thinking about changing the MB, but I'd prefer to leave it as a last choice (more $$..mmm too bad )
Thanks in advice,
Zack

 

Try this... http://www.majorgeeks.com/Driver_Cleaner_Professional_d3214.html instructions are in the Readme file. Good Luck.

 

does the blank screen only occur in windows or from the time you turn the computer on.

if you get a blank screen from when you turn the computer on, it wont be a driver problem. Your computer is not correctly detecting the card. You may need to reset the cmos to get the card detected. If you do this you will need to reenter any custom changes you have made in the bios, ie raid settings and the like.

If its only in windows then its most likely a driver problem.

 

The blank screen happens immediately when I turn the pc on, so yes I'm guessing it's a detection problem due to my shitty Azza motherboard.
By the way, updating the bios didn't solve anything.
I'll try to reset the cmos.
Thanks to both of you, if you have more ideas let me know
Zack

 

also, this may be a silly question, but have you connected power to the auxillary power connector of the video card. Try to plug the video card on a connector lead that has nothing else (e.g. hard drive) attached to it.