After updating my OS from Windows 8 to 8.1, I have started to expierience wierd keyboard lag. I mostly notice this when gaming. When I am pressing a key for a longer time, it gets "stuck" for a few seconds, and all other keys become unresponsive. I had this issue last time when I upgraded to Windows 8.1, only this time I don't have mouse lag. I am using a Samsung laptop with a Microsoft USB keyboard (My main one) connected, because I had some broken keys on my laptops keyboard. Now my laptops keyboard is replaced, but I use the USB keyboard for gaming, because I am used to it. I have installed all the latest updates, and I am waiting for Windows 10 reservation. Sorry for my bad english..