What exactly do you want to change? The priority of the idle task? The priority of WC3? The fact that it doesn't use much of the CPU when the computers lags (you won't be able to because the CPU is what does work on the data received during the game and less data means less processing)? You have less data coming in when you lag and therefore the CPU doesn't have to work as hard to process it. You would do better to find out what along the path from you to the others is causing the lag. Maybe it's some usage spikes from other computers set to check for anti-virus updates at a specific time or maybe it's not even something within your control but a router somewhere along the path is running a self-diagnostic periodically. Regardless, there is no point in trying to increase CPU usage when there is not enough data to process for the CPU to being with.
