The problem is related to how the system handles the live tiles in the Start screen. This happens when a tile update request set aside a portion of RAM and never returns to the main system memory. When this continues to happen during a certain period of time, the memory allocated keeps growing to the point that your PC runs out of memory. Microsoft already knows about this issue, but has yet to release a fix. Now, until a solution arrives for the Runtime Broker problem and if you experience sudden high memory usage in Windows 8, you can either try to end the process from the Task Manager (Ctrl + Shift + Esc keyboard shortcut) or uninstall any Windows 8 app that you think is causing problem — Restarting the PC will also help. Source Microsoft forum via Lifehacker All content on this site is provided with no warranties, express or implied. Use any information at your own risk. Always backup of your device and files before making any changes. Privacy policy info.