While you have the box open, you might consider an upgrade.
1) Find out the make and model of the main board.
2) Go to the manufacturers site and see if they have an upgraded BIOS code for you.
3) Consult with webpages that deal with upgrading and overclocking such as Jan Steunebrink's outstanding Overclocking websites.
http://web.inter.nl.net/hcc/J.Steunebrink/
4) Flash-upgrade your mainboard's BIOS.
5) Definitely invest in all the RAM you can afford.
6) Consider an upgraded CPU.
Places like z-buy, upgrade-solution and baber can give you some great deals on very inexpensive CPU's or even CPU/Mobo/RAM package deals
http://www.baber.com/baber/products/entry.htm http://www.upgrade-solution.com/
7) If you want to go broadband, it is very likely that you will need a network card to talk to the DSL / Cable modem.
8) If you overclock, pay close attention to proper flashing procedures, CPU voltage settings and CPU case cooling.
Yes, it's a bit of work, but for some, a lot of fun.
Cheers,
KJ