Dell motherboards are designed to be different than your typical board. Even if you open up your dell PC you will see its on the opposite side of the computer then it should be. The idea behind this is that it eliminates technicians from messing around with them too much. Its their way of making sure that they are the only people who can fix them.
If I were you I would look on eBay for a new one. Its not uncommon fto find people who were lucky enough to get their hands on new dell parts to sell them on eBay.
A Dell Dimension 8100 tend to be priced around $200. This price varies depending whether or not the product has been used and what condition it is in.
T5600 Motherboard
No (EIDE only)
You can purchase a Dell Inspiron 8100 online from auction websites such as eBay. Alternatively, you can purchase a Dell Inspiron 8100 from Craigslist.
Unfortuntely, the Dell motherboard form factors are propietary, so you'll have to buy replacement motherboards directly from dell.
$200
It is an ATX motherboard. But even though it is an ATX size it is a company specific motherboard, and is not compatible with standard ATX cases.
Short of buying a new motherboard it is not possible to fit a PCI-Express graphics card in a Dell Dimension 1100.
The Dell Dimension 3000 made its debut in 2004.
A Dell Dimension 2400 can be downloaded right from the Dell website directly. There is a site called Tom's Hardware that a Dell Dimension 2400 driver can be downloaded. A website called Solvusoft has a website that a Dell Dimension 2400 driver can be downloaded.
It is often hard to fit an after market motherboard into dell computers, you would have to check the dell website.
One might purchase a Dell Dimension 4500 from the Cputopia website. The website offers a variety of Dell made products, including the Dell Dimension 4500.