Vista RTM runs fine, Media Center flickers and crashes

Anyone else experience issues with Media Center on Vista Ultimate RTM?

I installed Vista, the built in Vista drivers for my AGP (256MB) verto card
worked fine - recognizd and installed correctly. I had some challenges with
the Linksys WUSB45GS wireless adapter, but got that working too, as well as
got the envy sound drivers from Windows Update... all was great... then I
tried to get into media center.. screen started going nuts.. flickering,
color blotches everywhere... and it froze.. same effect every time.. hard to
power down the PC (if I did justr a reset, the screen came up the same way -
blotches - during the reboot). power down reset the card and Vista worked
again - but same issue with media center...

ran into this in RC1 too - Beta Vista was fine though (both 32&64 bit)

So... I was wondering if my card is flaky or if the driver somehow has
issues with this card.

any ideas?

Thanks in advance for your help!

/Nick