Back with some more info....
You might want to look at this post in that we'll start with the same approach for your case.
If you look in your DxDiag report, to find its list of System Devices you'll notice that in your case these devices don't appear to have drivers listed
Code:
Name: Intel(R) 82865G\PE\P Processor to I/O Controller - 2570
Device ID: PCI\VEN_8086&DEV_2570&SUBSYS_00000000&REV_02\3&172E68DD&0&00
Driver: n/a
Name: SoundMAX Integrated Digital Audio
Device ID: PCI\VEN_8086&DEV_24D5&SUBSYS_01741028&REV_02\3&172E68DD&0&FD
Driver: n/a
Name: Intel(R) 82801EB SMBus Controller - 24D3
Device ID: PCI\VEN_8086&DEV_24D3&SUBSYS_01741028&REV_02\3&172E68DD&0&FB
Driver: n/a
Name: Video Controller (VGA Compatible)
Device ID: PCI\VEN_10DE&DEV_0028&SUBSYS_02011043&REV_15\4&1246FE7B&0&0008
Driver: n/a
Just as described in my other post, i'd like try getting the drivers for the first three in the list then we'll move to your graphics card.
The one other issue (as i noted above) is this business of dell model 4600 vs. 4600c vs. 4600i. (I keep seeing it reported as 4600i. Yet if i go to Dell support and enter model information it only provides a choice between 4600 and 4600c)
When you went to the Dell site
=> did you allow them to scan your computer?
=> Could you give me the link to the driver download web page they took you to?
=> Do you know / see the model number on your computer? A