Inspiron 9300: GeForce 6800Go giving up the ghost

I have a dying W5373 card in my Inspy 9300--after eight years, it's barfing up artifacts even on the BIOS screen, and kills the monitor after the Windows startup screen unless I run in Safe Mode. (Funny thing, once into Safe Mode all the artifacts go away.) Got a 6300-0119 error on Diagnostics, which every site I've checked says usually means "replace video card". Also get a 1000-0141 and 1000-0146 on hard drive, but since the drive itself is still working and I can still get a 320GB IDE internal at Fry's (currently have a 250) that's not an issue, I can just buy a new drive and use DriveImage or Partition Commander to migrate over.

I also appear to have lost my Windows XP Pro CD, so any driver replacement that needs it could be problematic. (Either that, or I need help with procuring another XP Pro install CD... and hope it can be used to repair a preexisting install without needing to reinstall.)

Can I just drop a C5846 GeForce 6800 Go Ultra in on the same driver, or for not fighting with drivers do I need another W5373 card going in? Also, I heard somewhere that Inspiron 9300 BIOSes A04 and A05 will support the GeForce 7800GTX without needing to reflash with an XPS Gen 2 BIOS--is this correct?

Thank you!