Earlier my desktop was to b in d same place where the router was der. Everything worked fine. Now I decided to shift my desktop to another room. I have kept the router at the earlier place only. I have brought a 25m long new cat 5 cable. When I connected it to my desktop, the orange led on ethernet port do not light up and the desktop is unable to detect the ethernet cable and hence the internet connection. On the router, a light of ethernet keeps on blinking every 1 second. I was worried whether my ethernet port got fried. So i inserted another ethernet cable, but then the ethernet orange light came and the pc detedted the connection. Therefore I thought the cable might be faulty. Therefore I connected my laptop with that 25m cable. But my laptop detected it and showed the internet connection. But now when i again connect the cable to my desktop, there's no light and the pc does not detect it. However, if i connect the 25m cable to my desktop then during boot the ethernet light on router is stable just as when it is normally connected to the internet. But when i go into windows it starts blinking every 1 second.
My router is MTNL Model No. UT-304R2
Desktop - Asus P7H55, core i5
Laptop- HP 2000
Windows 7 Ultimate on both desktop and laptop.