So we have bought 34 of these Dell Optiplex 990 Desktop PCs. About 50% of them I can get the WOL option to work. They are all the same configuration and they are all the same OEM image from dell. Other than windows updates these are pretty plain machines. To enable I went into the bios and turn on "WAKE ON LAN" to "LAN only" as that's the only option. I then go into the network interface and under power management I check the box "Wake on Magic Packet and Wake on Pattern Match" These are Intel 82579LM Gig Adapters on the board. Again about 50% seem to work just fine. I can put them into sleep mode and send WOL and it wakes up. In digging into the ones that don't work I found out that if I run from cmd elevated "powercfg -devicequery wake_armed" The ones that do work have the "Intel(R) 82579LM Gigabit Network Connection" Listed, but the ones that don't, don't have it listed. So i tried "powercfg -deviceenablewake "Intel(R) 82579LM Gigabit Network Connection" which adds just fine, but on a reboot it's not there. So it's like the setting does not take. Also with the intel driver there isn't a check box to "allow this device to wake the pc" option. Any help would be great, Dell's tech support blows so their no help. I guess I could call MS, but they may just point to intel. BTW running windows 7 pro.