Whew!
(I need a drink......)
Anyway, a celeron 366 or above with sdram would give you twice the computing power. But you pay just as much for that system (new) as you would an duron 600.
Figure (without s/h) 85 for a motherboard, 60 for a processor, 35 for a bit-o-ram, 25 for a heatsink, 9 for some arctic silver, keep the sound card (isa), keep the vid card (pci), keep the hard drive (8 meg/sec read), keep the case (atx factor), $30 for a 300 watt power supply, 12 for two new ata-66 cables, keep the floppy, keep the cdrom reader.
Probably under $200.
Check out <A HREF="http://www.pricewatch.com" target="_new"> Pricewatch</A>