I’m sorry, I don’t think I fully understand what you are asking…
If you are worried about the Mybook Live causing lag to your online games while it is backing up your computers, then there should be no problems.
The Mybook Live traffic will only use the LAN side of your network whereas the online games would be primarily be affected by the Internet side of your network. Most network interface cards can handle whatever you throw at them (for home user purposes). I guess you could always adjust IP QoS for the Mybook Live in your router’s config settings if you wanted a bit more control.
If you are asking about whether the backup will cause additional RAM/CPU usage on your PC’s during online gaming, then I imagine it would. Provided you are not running ancient computer hardware, you shouldn’t notice too much degredation.
