First build help

Hey, I have a Dell and just found out upon opening it , that it is near impossible to upgrade so I am looking at getting a new motherboard(and case)possibly later some more RAM and another hard drive, however I have lots of spare parts laying around I am hoping to reuse.

my main query is how to find out (without opening the case it is a real hassle and boxed into a corner) what "socket" my processor needs (intel P4 2.80Ghz) and anything else I need to check to make sure it is compatible with a new motherboard
Also how do I find out similar things for RAM, dvd drives, hard drives, graphics cards, network cards, etc

which if the endless list of specs do I need to check for compatibility

thanks so much for any advice or links

Check Dell's website, you just type in your model ID number and it should give you the whole shebang. Otherwise, I'm sure someone with more patience will type out all the things you need to check.

>>1
Just take the plunge, you'll learn more. You're gonna open it anyways. Anyways, are you upgrading it? If so, why are you getting a new motherboard for an old CPU? Makes no sense. If budget is important, get a 965/975 motherboard, a cheap Pentium D (like a Presler 930 for example), 1gb Corsair DDR2, new PSU (like an Antec, or Epower/Tagan or Enermax). Assuming you want to go Intel. You could buy a cheaper AM2 system, with like a X2 3600+.

To find out what you have now, CPU-Z is a good, simple, stand-alone solution. Everest is good when you need something more thorough.

Though Everest or CPU Z will be able to actually tell you, I can be pretty sure that If you bought it more than 2 months ago, less than like 3 years ago, that 2.8GHz CPU is PROBABLY a Prescott, (maybe a Northwood if on the older side of 3 years) on a socket 478 mobo, with DDR 266/333/400, 256 to 512 mb of it, would be my guess. Can't say much more specific than that, since I'm not there to look.

If you go with my suggestion for a new motherboard, CPU, RAM then you'll still be able to reuse the old HDD, optical drive, monitor, possibly the case as well. Might still need new PSU though.
If you keep the CPU, you'll be wasting your money on an architecture Intel abandoned some time ago. For Intel, socket LGA775 (aka socket T) is where it is at. For AMD, it is AM2 (though 939 is still workable if you don't want to upgrade again the future) I mean, you COULD upgrade to an Extreme Edition Prescott, on that 478 board but it will cost more, run hotter, perform signifigantly lower than a budget or mainstream socket 775 processor. It seems cheaper, but in the long run, you will regret it.