I have two routers that are acting really funky - both are used and acquired secondhand somehow, so I am willing to accept the inevitability of them being toast.
Anyway, the Netgear WGR-614 is what I currently have plugged in and running. I have AT&T DSL with a SpeedStream 5100 modem. I have flashed the router several times and redone the settings. The network is currently protected with WEP 64 bit (don't moan - I have hardware that won't do WPA). I have the network broadcasting on channel 6 after discovering that almost all of my neighbors use channel 11. MTU is at the default 1492 (max). I made sure to put the router on a different subnet so it wouldn't conflict with the modem (192.168.2.1). Even still, the most peculiar thing is happening. When it is just me using the internet, everything is golden. As soon as my roommate connects, the connection becomes sluggish and practically unusable, and usually, it will render his connection "local only" on his Vista (groan) machine. My Ubuntu machine still stays connected, but barely. There is no IP conflict occurring between our two laptops, but it refuses to connect more than one device. Oh, and I HAVE tried updated hardware. It's just odd because it worked perfectly last year when I was running cable internet. It just sat unplugged over the summer and now won't work.
The second router is a D-Link DI-624. I've flashed it several times, but no matter what, I can't connect to it via wireless or with the LAN port. No wireless network shows when I scan (even with aircrack). When I plug in with an ethernet cable, my computer doesn't see it, and nothing lights up on the router to show a plugged in cable. The ONLY time anything gets detected is when I plug into the WAN port. It lights up and my computer starts to negotiate (not with a crossover cable), and then it fails. Odd. Any thoughts on saving it, or is it trash?
In this situation I would isolate the Dlink 624 other than a single ethernet cable to it from a computer. Press reset to clear any mis-settings and address the router's setup screen just to ensure that wireless is on (any channel) and broadcasting SSID.
Then disconnect the cable and try detecting the router's wireless with the computer still in the same room. If no joy, router's wireless is probably shot or the power supply cube to the router is under-voltage.