Radeon 9800 pro 256mb hanging on blue screen

Question

I'm deep in the waters of frustration right now, and am hoping someone here might have the answer.
About 3 months ago I was looking for a video card for me to run motion. I saw the 9800 mac special edition with 128mb video ram had rave reviews. At that time ATI was not making them. So I turned to eBay...
I purchased a card that was advertised as a Mac 9800 pro special editing 128mb. I later found out it was a flashed pc card. The ebay seller told me the card worked fine on all his mac's that he tested it on.
The problem I was having was the machine boots up, I see the grey screen with the Apple logo and spinning wheel. I see the blue screen where normally I see the login progress bar loading the OS. But with this card I only see the blue screen. I hear the hard drive churning, so I am assuming it is still loading the OS, but I cannot see anything. I can reboot in safe mode and the video card works fine.
Well... I assumed it was the fault of the card and that it was flashed. I returned the card to the ebay seller, who sent me another one, same results with that one. I returned the card to the seller and he refunded my money.
I put the money toward the just released Radeon 9800 Pro Mac Edition 256mb card. I just got it a couple days ago and am experiencing the same problems. I have tried everything... everything I know and still can't get the card to work? Here is a list of what I have done:
With the flashed card:
1. Shut off computer and unplugged it. Removed OEM video card and installed ATI 9800 card. Plugged the power supply cable for the card into the computer power supply cable and hard drive.
Problem Occurs: When starting up, the grey screen comes up with the Apple on it, then the screen turns blue, where I typically would see the progress bar of the system loaded up before the user login screen. I only see a blue screen at this point but can hear the hard drive working for about a min.
2. Restarted the computer in safe mode.
3. Logged in as Admin user and opened the ATI preference pane to verify it sees the card.
When the ATI preference pane was loaded the following error message occured:
A startup problem has occured.
Cannot connect to ATI TVOut Kernal Extension. Some features are not available.
Clicked OK and the ATI preference pane appears.
4. Close the preference pane and reinstalled ATI Displays 4.5.6. Restarted computer.
Problem Occurs
5. Restarted computer holding down AppleOption+PR to clear PRAM. Cleared the PRAM 4 times in a row, by allowing the chime to happen 4 times.
Problem Occurs
6. Shut computer down. Disconnected the DVI plug for the cinema display and connected a VGA CRT monitor. Started computer.
Problem Occurs
7. Shut computer down, disconnected the VGA CRT monitor. Reconnected DVI plug and restarted computer.
Problem Occurs
8. Started the computer in safe mode. Logged into admin account. Opened the ATI Preference pane.
When the ATI preference pane was loaded the following error message occured:
A startup problem has occured.
Cannot connect to ATI TVOut Kernal Extension. Some features are not available.
Closed preference pane.
Went to ATI site and downloaded:
aug2005-radeo-universal-rom-update.dmg
Ran the updater.
Restarted computer.
Problem Occurs.
9. Restarted the computer in safe mode. Changed the login preference pannel to automatically log into the administrator account. Restarted computer, waited for the blue screen, then walked away for about 2 hours with the computer on blue screen, hoping the system was loading or doing something.
Problem Occurs.
10. Put in the TechTools Pro CD, hoping to run some tests on the video card from the cd. When booting from the CD OS...
Problem Occurs.
11. Enabled Root user. Logged in as root and installed ATI Displays 4.5.6 from there. Restarted computer.
Problem Occurs.
12. Shut down computer and installed old video card.
13. On an internal hard drive in the computer. Wiped the drive and formatted it. Installed 10.4.1 on the drive. booted up into the drive, installed ATI drivers, shut down computer, installed 9800 pro video card, booted up.
Problem Occurs.
With the new 9800 for Mac ATI card with 256mb:
With original card, install drivers, repairpermissions, shut down, install new card
Set to restart in single user, give 5 min to see if ATI monitor startup item in user starteputems loads
Hooked VGA & DVIt in together, both showed blue screen
Reset NVRAM via open firmware
Reset cuda button
Take battery out, wait at least 10 min, re-install new battery, press cuda button
Reinstall ATI update 4.5.6
Reset nvram from open firmware
In ATI control panel, selected 'Force Single Display Operation'
Change display scaling to 50%
Download latest Mac OS update from apple & reinstall
Help?

Answer 1

I get dizzy just thinking about it.
I have tried installed a brand new OS, 3 different times on a different Hard Drive, still the card doesn't work.
I had one person suggest that it may be the card is not communicating with the OS Window Drawing module? (excuse my ignorance of what that is really called. I just know there is some program, possibly in the kernel, that is responsible for drawing out the OS windows.)
How can we rule out that it is a bad AGP slot?
•The slot works fine with my 9000.
•It works in safe mode with the 9800.
•I have installed a brand new OS, three different times, still doesn't work.
•I have used Apple Hardware test to test my hardware, the AGP slot didn't report any problems.
I am assuming that the AGP slot is working. Although I worry about it a bit, because by now I have swapped cards in it about 50 times in my troubleshooting.
Here is a link to a complete list of everything I have tried:
http://www.macosx.com/help/qview.php?questionid=19554#54138