2. EthMon - available for Win and Android
3. Connect the monitor to the primary GPU (X16_1 slot)
I use Linux, so don't have anything good to say about using Windoze.
Instead of connecting a monitor to the primary GPU, I recommend using the on-board video for the display. You can often overclock cards a bit more when they don't need to do video out. It's also easier for testing GPUs since you just leave the video cable plugged into the motherboard.