Disable onboard graphics.

You gotta go into your BIOS and disable the onboard graphics.  However, there's a chance your current BIOS doesn't have that option.  For that, you will have to download the latest flashBIOS from Dell.  I'm running into the exact same problems you are...only, I have an nvidia asylum 256mb pci card.  After I plugged it in along w/ the drivers, I got a bunch of errors about the video card not starting.

I just found out some of this info, so i'm gonna check it out the next time I see my PC and see if it works.

There was also alot of talk about switching the new video card around...from one PCI port to another, or plugging it into the PCI slot farthest away from the motherboard, etc etc....basically, it's a headache...but something we gotta deal with if we want to upgrade the 2400's graphics capabilities.

Try these tips from one of the Dell techs

2200, 2300, 2350, 2400 -
* Click Your Dell Home Page
* If asked, click Home and Home Office
* Is your System/DJ/Axim listed on the left under "Your System"? If not, click "Select a System"
* Enter your System/DJ/Axim Service Tag (found on the back of the System/DJ/Axim)
* Click Go
* A cookie will be placed in your system to remember this data in the future
* On the left, click Product Manuals
* Click Adding Parts or Tech Notes, look for "opening the computer cover" or "Removing and Replacing Parts". Read this section
* Power down and open the case
* Insert the new video card (Ati 9100) in a PCI slot
* Connect the monitor to the added video card
* Restart the computer
* At the first beep (older systems) or on the blue Dell screen (new systems), tap the F8 key (do not hold it down)
* At some point, the Advanced Options menu will appear
* Scroll to and select Safe Mode [press the Enter key]
* At the operating system listing [press the Enter key]
* Windows will start in Safe Mode. Close any boxes that may open, just get to the desktop
* Press the Windows + Pause/Break keys
* Click the Hardware tab and/or the Device Manager button
* Open Display Adapters
* Right click the Intel listing
* Click Disable
* Click Apply or Ok. Just close all the boxes
* Click Start- Shutdown- Restart- OK or Click Start- Turn Off Computer- Restart
* The added video card will be found and it will ask for drivers

Primary Video Controller not seen in the bios? Flash the bios -
* Click Your Dell Home Page
* If asked, click Home and Home Office
* Is your System/DJ/Axim listed on the left under "Your System"? If not, click "Select a System"
* Enter your System/DJ/Axim Service Tag (found on the back of the System/DJ/Axim)
* Click Go
* A cookie will be placed in your system to remember this data in the future
* Click the tab or button Downloads
* 1. Select FlashBIOS Updates
* Click Go
* Under FlashBIOS Updates, click Dell Dimension System BIOS
* Under FlashBIOS Updates [BIOS], click Dell Dimension System BIOS
* Click the first file listed
* Click Download Now Using HTTP
* Click Save
* Click Desktop
* Click Save
* After downloading the bios update file to your desktop:
- Insert a blank floppy disk into the 3 1/2 drive
- Double-click the file you downloaded to the desktop
* Follow the instructions to create a 'bootable' diskette that contains the BIOS update
* LEAVE THE DISK INSERTED, Click Start- Shutdown- Restart- Ok or Click Start- Turn Off Computer- Restart and the system will prompt the user for any required input while performing the BIOS update process
* When the flash is done, remove the disk and reboot the system and go back to the first set of instructions

Yeah.  that was another thing I wanted to figure out.  if we don't have a floppy drive, then how do we get the machine to go ahead and revise the flashbios.

Yeah who uses floppy drives anymore? hahahh sigh.

Wow....that's the same card i'm trying to plug into my 2400.  Those instructions are still helpful since you can try the same steps for the geforce 5200.  Well, if it works for me, then it should work for you...and vice versa.

Installing the PCI card and drivers wasn't difficult.  It's just the problems with conflicts and tweaking that's becoming a headache.  I won't be able to work on my machine til either tomorrow or tuesday.  Hopefully then I'll have it working and post the steps on here.

ok right, there are two scenario's. either you've installed the drivers for your current card, and its not working, or you have yet to install the drivers. here's what worked for me.

1. connect your video card into a slot.

2.connect your monitor to your new video card.

3. switch on your computer

4.press F8 at the dell screen.

5.go to advanced options and choose to start windows in safe mode.

6. possibly press windows + pause/break keys (can't remember if i did that step but it won't do any harm

7. get to the device manager

(right click my computer, select manage, then go to device manager)

8. in display adapters disable intel extreme graphics

8.b (optional) uninstall drivers for your card (if you installed them, I'm not sure if thats neccessary, i did it just to be on the safe side)

9. reboot

10.new video card is found drivers asked for etc etc