transfering files to 2nd PC kills its connection

[HydroSqueegee]

So ive setup a second PC here and hooked it up through my linksys router. I go to transfer some files to its drive and after about a minute, i lose my connection to the 2nd box and cant get it back unless i reboot it, but the first PC works fine.

2nd PC is running an asus a7v8x-x and is using its onboard network adapter. Any ideas as to why it may be dropping?