My Gigabyte EP45-ud3p have 2 onboard lan slot. Since yesterday i was using the second onboard lan slot in the mobo, and its work fine. And today,when i on the pc and i cant connect to internet. I realize that green and yellow light in the second onboard lan slot do not blink. Further more the icon of local area connection show NETWORK CABLE UNPLUGGED. When I check the device manager of the 2 network adapter realtek RTL8186C ,its stated work properly. So I try to switch the lan wire to the first onboard lan slot and can connect to internet. Is hardware problem or software problem?
GhislainG and soundefx, thank you so much for your kind reply and I really appreciate it. Today I send my pc to the shop I bought it to claim warranty. When the technician plug Lan wire into the problem lan slot, its work perfectly. And he also tried to connect internet Wifi using his USB Wifi adapter. So he install the USB wifi software in my pc. After the software was install in my pc, the technician unable to find the Wifi program that he was install. He say its software problem that may caused by spyware or virus. So he advice me to format the pc. Tomorrow I will save all my media files and try to format my pc.