I know now that this is a Desktop motherboard, officially not supported for Windows Server operating systems, but I would still like to get it to work. I've confirmed that the motherboard network works in WinXP (Intel 82579V Gigabit) and typically the 32-bit Windows XP drivers work on Server 2003 as well. Several of the other drivers have installed just fine, but the network driver install package fails with "No Intel Adapters are present." When I try to manually point the driver update to the downloaded package on the CD or extracted (7zip) from the download it doesn't find what it wants. I am trying to install Windows Home Server v1 (based on Windows Server 2003) on this box and just want to get a basic network driver up and running. I've checked the BIOS config, and Device Manager shows a yellow question mark by "Ethernet Controller". The ID is: PCI\VEN_8086&DEV_1503&SUBSYS_20408086&REV_04\3&11583659&0&C8 but I don't really know what to do with that...
I recently ran into a similar problem trying to get the WHSv1 restore CD to see my onboard NIC. Like you I extracted the x32 drivers from Intel's installer using 7-zip and copied them over to a flash drive, but Windows would fail to detect and install the hardware.
It turned out that the problem wasn't that Windows couldn't find the driver I placed on the flash drive, it couldn't find the NIC in the first place. It needed additional drivers for my motherboard to see the PCI bridge (or something or another) before it could detect the NIC in the first place.
I wasn't really sure what exactly it was that I needed, so I went to my motherboard manufacturer's site and downloaded every WinXP/2003x32 compatible driver they listed and tossed it onto the flash drive and let the hardware wizard figure it out. I can't be certain which of those drivers it needed, but it worked.
Intel usually packages many/all of their network drivers into one package, so you should try the 'generic' Intel PROSet driver set for Windows 2003.
If you search for the Ethernet chipset you've said you have (as I just did), Intel's ARK reports it as needing the same driver.
The latest version (currently 17.3) is available from Intel's Download Center here.