I have a Dell Demension 3000 that I purchased in 2004. It has a Intel Celeron processor. I am pretty sure you can't do this, or it's not very common, but I wanted to put in a Intel Core 2 Quad, or a Intel Core 2 Duo. Could I do this?

Intel Core 2 Quad:
http://www.newegg.com/Product/Product.aspx...N82E16819115017

Intel Core 2 Duo:
http://www.newegg.com/Product/Product.aspx...N82E16819115028

Thanks in Advance!

First off, I think you're wasting your time. Your system is 4 years old. Even if you had a Socket 775 motherboard and the chipset could support a Core 2 Duo processor, would Dell release a BIOS that would allow it? I think not. You have an Inspiron--their idea is sell you a new computer every 2-4 years and you keep coming back for more. Furthermore you probably have DDR RAM and AGP graphics (or integrated graphics, as suggested by an Inspiron series), all of these factors are out-dated. Your power supply as well would likely not be able to supply enough power, and is likely not even pin-compatible with a new board.

Save your money and just buy a new computer, or build a new one and just reuse the basics (optical drives, hard drives).