new build only connects to internet when connected to modem

[reinise]

my newly built pc only connects to the internet when directly connected to the modem. when connected to the Linksys WRT54G, the internet does not work and there are no status lights on the ethernet port on my computer. however all other computers and devices, wired and wireless, all work with the router. my new computer is the only one that doesnt work with the router.
i have:
1. reset the router and the modem
2. updated all drivers
3. checked to make sure the cable is good and the port on the router is good (they're both good, i use this ethernet cord and router port for my xbox and it works fine.)
4. DNS and DHCP are enabled
5. i've worked on this crap for 3 days now so ive done a lot more trouble shooting than this, i just cant remember everything.

any help would be much appreciated, thanks!

 

[chev65]

The obvious solution is to update the firmware on your WRT54G. You need select the correct hardware version for either of these.

Linksys WRT54G

The latest DDWRT firmware will also work and has more options in the firmware for networking.
Router Database | www.dd-wrt.com

 

[reinise]

good idea, i think that's the only thing i haven't tried. however, when i tried it, it failed every time. i tried other versions just to see, and they all failed. i also tried the DDWRT thing, it also failed.

 

[reinise]

I also called my ISP, they knew nothing and were of no help. I also called Linksys, they knew even more nothing than my ISP. so that was a wasted hour.