Microsoft explains why Task Manager freezes under heavy CPU load

Microsoft engineer Raymond Chen said raising Task Manager's priority won't fix freezes, since a high-priority thread still waits on a resource held by a slower thread. When the CPU is starved, the taskbar and Task Manager suffer too, even though they are the tools users rely on to kill a runaway app.

• Windows priorities from 0 to 31 only decide who gets the CPU first
• A thread waiting on a lock or file isn't even queued for the CPU
• AutoBoost raises the resource holder's priority but can't speed up a slow network
• Ctrl+Alt+Delete or End task from the taskbar can help when it freezes