Lan part in my router is not working

hi everybody,

i have a problem. i want to know wat exactly is not working. i have a smartax mt882 router. i can be connected to system via ethernet or usb. for the past 2 years i have been using internet via ethernet port. my bro bought a laptop. so i wanted to connect both my pc n his laptop via ethernet for lan games. then i started using usb for my internet.

it was fine. all worked well. at times my bro will use internet via ethernet port in router n i ll use via usb.

suddenly one day his lap showed network cable unplugged. cable is connected well. lan bulb in my router is off. i though his lap could be a prob so i tried crossover lan between my pc n his lap. connected succefuly. so his lap is good. my sys lan also good obviously.

now i removed usb n tried to connect my sys n router via lan. same problem. netwrok cable unplugged. lan bulb in router not glowing.

i think lan part in my router is not functionin. USB works well.

solutions tried:

restarted router/modem
reset to factory settings

in command promt when i checked ipconfig

it showed media disconnected in my ethernet part.

wat could be the problem. should i buy new router.

lan calble worked well with crossover lan connection between my pc n lap.
so cable is fine i suppose

is it possible to get my lan part alone fried in my router...i wonder why the whole router didnt fry... atleast i m lucky to get my usb working...warranty over...

shall go for repair or buy a new one?