Logitech mice beomce laggy and innacurate when the CPU is under load. This does NOT mean that the system has inadequate resources, I mean that when the PC is doing LITERALLY ANYTHING other than idling, Logitech devices become laggy, innacurate and unreliable. Whatever system you have employed in Options is not working. USB dongle is right next to the mouse with clear line of site. Tested with MX3s, Triathalon etc: ALL have the same problem so the problem is in Options. MX3s is a $100 peripheral and currently unusable: Pleas fix options ASAP so we can all get back to work