It sounds like you experienced performance issues after upgrading your RAM from 2GB to 4GB on your Windows 7 system. Here are some steps you can take to troubleshoot and potentially resolve the high CPU usage problem: 1. Check RAM Compatibility: Ensure that the new 4GB RAM module is compatible with your motherboard and that it is seated properly in the slot. 2. Update Drivers: Make sure all your drivers, especially those related to chipset, graphics, and audio, are up to date. Outdated drivers can sometimes cause high CPU usage. 3. Check Task Manager: Monitor the Task Manager to identify which processes are consuming the most CPU resources. Look for any specific process that stands out and might be causing the high CPU...