Solved problem, thought I'd post if anyone else with a Realtek onboard nic runs into the same problem. This was on a MSI H55-G43 with Win7 x86. Had a problem with one of the home pcs today, came out of sleep (S3) and there was no internet. Check that...no network controller at all. Didn't show up in hardware manager, nothing. Restart, same thing. Reinstall drivers, same thing, with a great error message, "If deep sleep mode is enabled Please plug the cable." Checked BIOS, onboard LAN is enabled. Reset CMOS. Standard troubleshooting. After an hour of digging through forums etc. and trying different suggestions, found a real stupid one..."I found the fix: power down and unplug the PC. Do a little f---ing dance, power back on and it works." Apparently that's what "please plug the cable" means. Aaaaaand, that solved it. Apparently these nics have a problem waking up from "deep sleep" and you need to nudge them out of it. To keep them from getting to this state: - Go to Device Manager - Select Network Adapters - Select Realtek PCIe GBE Family Controller - Select Power Management - make sure "Allow the computer to turn off this device to save power" is unchecked - Select Advanced - under Green Power, select Disabled. I think the Green Power one is probably unnecessary but not taking any chances. Anyway, hope this helps anyone who may run into the same problem. This isn't 100%, there are threads out there where this has been tried and still doesn't work.