Why did RDRAM and Socket 423 go so obsolete so quickly?

I have the one of the first Pentium 4's to come out which is the 1.3Ghz. Willamette core MMX, SSE, SSE2 256KB Cache and 2 128MB'S of PC800 RDRAM and a 60GB HDD a CD-R/RW which doesn't work. Antec case a 600 Watt power supply. Is this machine so obselete? what can i do to improve it? It has a nVidia GeForce2MX/MX400 64MB Video Memory for the video card.