or you should better check settings on your router so you can leave power saving enabled to save battery, check if there are any option for enabling power saving mode support and see also beacon interval and DTIM value, do not set it insanely high or bigger lag will appear. beacon iterval*DTIM is how often tablet wakes to check for queued data packets so 200 and 1 (or 100 and 2) makes it 200ms, 200 and 2 makes 400ms packet delay. see also dmesg log on tablet after you connect to network, those values should be logged so you know how they are set, search for 'associated to xx:xx:xx... (bcn xxx msec, DTIM y), I see bcn 100 msec, DTIM 1 here now for some random asus router of my colleague