PCI Device/Network Card Missing..PC HELP?

[bobberbiker]

hey guys
im on the verge of taking a hammer to my pc. can someone help me out.

i have 2 computers and the 2nd one keeps saying my pci device is disconnected. it was working fine then 1 day it just didnt recognise it so i cant connect to the internet, iv triple checked cables etc i didnt change anything at all on it for it not to work, sometimes it will connect when i turn the pc on maybe once a week then the next day it is gone again. its a e-machines and windows XP. i have no idea what to do iv tried everything i can think of.
any ideas?

iv reinstalled xp and still no luck, it says found new hardware but wont install it so its got the yellow question mark next to it on device manager. the network adapter shows up as working (realtek) but when i click connections it says its disconected/unplugged which it is not. iv not been able to use the internet for weeks now on that pc and its getting annoying now