Well, I know that I personally do not use a modem at school. The school probably has them in hubs somewhere, but the students do not use modems. Likewise here at the apartment, the housing owners probably have servers of modems somewhere, but they are not accessible by the tenants. We just plug into the wall for our internet.
So no, no modems. (At least that we can do anything with)
You are using your int. modem when you plug in. Hopefully it's a CAT5, so it's gigabit or at least 10/100. What specific routers are they? Linksys and Netgear? What Firmware? Wirelessrouters need 5 min to reset NVRAM and re-initialize. Do a hard reset(30/30/30) on your wireless routers before re-trying. Hold a pin on the reset button,(tiny hole on Netgear, small red hole on Linksys) for 30 seconds, then power off, (DO NOT RELEASE PIN) for 30 seconds, Power On, DO NOT RELEASE PIN, for 30 seconds, Okay Now relinquish your hold on the pin, wait ~10 seconds, turn it off ~10 seconds, then back on, give it five minutes to go through all of its light show, then it's a factory reset. Those routers can benefit from custom firmware, OpenWRT, DDwrt and Tomato. I use
dd-wrt
When you get your routers rebooted and go to logon on to the settings page, Wirelessly, you have to clear the browser cache. And reset your laptop wifi adapter.
1) Factory Reset Router
2) Acquire hardwire signal, CAT5 GOES IN YELLOW PORT ON ROUTER, COMMUNICATING SIGNALS IN OTHER PORTS!
2) Re-set wifi adapter on laptop, clear browser cache, log-on to access point, (admin/password, or admin/admin, or user/password, etc) Set-up router. Note everytime you change a setting and hit 'apply/update' , router has to update its dalvik cache-NVRAM, it takes 2 min.
(recently I was updating firmware{dd-wrt} into a NetGear N3700. I was using my tablet to CAT5 to router, no outside connections to the world. I updated the firmware through the web interface, and got no response, then I noticed New firmware, but it was corrupt, then my modem was a brick, upsetting, but no sweat, just a new process. TFTP. What had really happened was my tablet used its dual band wifi card to logon to an open local Netgear N3400, update his firmware, with all my settings, PW/login. I was able to get back in a week later, and set his stuff to default, boost his broadcast strength, but had to leave ddwrt in. You not supposed to be able to update firmware w/o hardwire. His system just had to reboot and it was fine. The netgear broadcasting 'dd-wrt' disappeared after a couple weeks, a cheap belkin G took its place. Still don't know who it is)