got "code 12" after installing creative sb X-Fi xtreme gamer

Hi.

I've installed a creative sb X-Fi xtreme gamer.
As result i've got a "code 12" error on my geforce 7800 GS. I get
only
4-K colors.


Tried different PCI-slots, flashed my bios, re-installed my Xp -->
nothings works


My system:
PIV 3.0 ; 2 gig DDR
Bliss 7800 GS 512MB (AGP)
Mobo Abit AI7


Can anybody give a solution?


Tnx in advance!


Fred