The Memory Bandwidth Vector
When assembling a custom PC or upgrading an existing rig, simply knowing the total capacity of your Random Access Memory (RAM) is insufficient. The speed at which that memory operates—measured in Megahertz (MHz)—dictates how rapidly data can be fed to your processor. If you have purchased high-speed 3600MHz RAM but your motherboard is incorrectly defaulting it to the base 2133MHz speed, you are leaving massive amounts of performance on the table.
How to Check Your RAM Speed
Before diving into the complex BIOS settings to enable XMP profiles, you must use Windows 11 to verify the actual, live operational speed of your memory.
1. Right-click anywhere on the empty space of your Taskbar at the bottom of the screen.
2. Select Task Manager from the context menu (or press Ctrl + Shift + Esc on your keyboard).
3. If your Task Manager opens in a simplified view, click the More details arrow at the bottom.
4. Click on the Performance tab (located on the left-hand sidebar or across the top).
5. In the Performance menu, click on Memory.
6. Look at the lower-right quadrant of the main window pane. You will see a data point labelled Speed:
The number displayed here (e.g., 3200 MHz or 4800 MT/s) is the exact, current operational frequency of your RAM. If this number is significantly lower than the speed advertised on your physical RAM sticks, you must reboot into your system BIOS to correct the configuration.