[G4] Is my Radeon 9800 128mb Mac card ok?

[deepthought]

Hi,

I just upgraded my video card to a 9800 128mb Radeon Mac edition card
and it worked great for about a day.  From day 2 onward, I got light
pink vertical lines running up and down across my LCD monitor.  They
appear on the whole desktop all the way up to the menu!

I have a Sonnet ST 1gz upgraded AGP Sawtooth w/ 1.5RAM and had a 8500
Radeon before the upgrade.  I am also running Tiger 10.4.1 .  
Everything was working perfectly before!

Thanks for any help!