Gateway E-4000 machine parts

[Stevenb]

I recently purchased a Gateway e-4000 for parts and when I plugged it in(I was surprised it worked) the little light came on but no sound came from the machine. When I opened up the machine it was missing the cpu, hard drive etc, basically only had the optical drive. It had the Windows XP Home edition with intel pentium 4. Is it possible to upgrade this? If not how do I get the exact same parts for it.

Thanks,

Steve