One other person, 1/2 bent, seems to have had some success. He actually soldered the two points. So, maybe the quality of the bridge is important.
I have tried many different bios changes over the last couple of weeks. I always flash from floppy so I have a backup of the current working bios and can flash back to it if something goes wrong. If someone has a floppy for their laptop then I can provide the exact utlity that I have been using. I have been using the flashing utility from techpowerup.com for the 12->16 pipe mod for x800 pro vivo cards.
I'm not sure what procedure that everyone has been following. Assuming you have already done the hardmod, Try this:
1) Uninstall all drivers and clean your system using www.drivercleaner.net
2) Uninstall your video card from Device Manager.
4) When windows detects your card at reboot just click cancel.
5) Clean your system again using the utility from www.drivercleaner.net
. To use the utility correctly I believe you have to boot into safe mode.
6) Make sure your video card does not show up under displays in Device Manager. If it does uninstall it.
8) Click cancel when windows detects the card. Install your video drivers.
I will try this procedure myself tonight after flashing back to the stock Dell bios. If I revert back to 8 pipe performance then we will know the bios does make a difference.