What GPU Shared Memory Is and Why It Eats Your RAM
GPU shared memory in BIOS is a setting that reserves part of your system RAM for integrated graphics, reducing the amount of memory available to Windows and your applications even when a discrete graphics card is installed and set as the primary GPU. On CPUs with an integrated GPU, there is no dedicated VRAM, so the system carves out a fixed chunk of RAM as a video memory pool. This is why Task Manager may show less usable RAM than you installed, such as 12.9GB usable from 16GB. For users with 8GB or 16GB of RAM, losing 0.5GB to 2GB to GPU shared memory can make the system feel sluggish in games, creative tools, or heavy multitasking. The good news is that this reservation can often be reduced or disabled in BIOS, restoring that memory to normal use.
Check How Much RAM You Can Actually Use
Before changing BIOS optimization settings, confirm how much RAM is accessible. Open Task Manager, go to the Performance tab, and look at the Memory section. Compare the “Installed” value to the “Available” or “In use (Compressed)” figures; a significant gap can signal system memory allocation to the integrated GPU and other hardware. If you installed 16GB but see something like 12.9GB usable, shared GPU memory or reserved hardware memory is likely involved. Close heavy apps and note how close you get to the usable ceiling during normal work or gaming. Users with 16GB or less who frequently hit 80–90% memory usage will notice the biggest benefit from freeing up RAM. This baseline check also lets you measure the effect after you disable or reduce GPU shared memory in BIOS.
Enter BIOS and Find GPU Shared Memory Settings
To change GPU shared memory BIOS options, restart your PC and press Delete or F2 repeatedly as it boots to enter the firmware setup. The exact key may differ, but these two are the most common. Once inside, look for sections named Advanced, Chipset Configuration, or Graphics Configuration; motherboard vendors group system memory allocation controls in these areas. You are searching for options such as DVMT Pre-Allocated, UMA Frame Buffer Size, or similar wording that describes pre-allocated video memory. On some boards, this is found under an Integrated Graphics or Internal Graphics menu. Note the current value (for example, 512MB or 1GB), since that tells you how much RAM is reserved. BIOS layouts vary, so move slowly and avoid altering unrelated settings while you focus on the graphics memory configuration.
Reduce or Disable GPU Shared Memory to Free Up RAM
Once you locate DVMT Pre-Allocated, UMA Frame Buffer Size, or an equivalent entry, open the option and choose the lowest available memory size to free up RAM. Many systems let you drop the reservation to tens of megabytes instead of hundreds, which can restore 32MB to 2GB of usable memory depending on your configuration. If you always use a discrete GPU and never rely on the integrated GPU, set Primary GPU to PCIe or disable integrated graphics entirely in the same Graphics Configuration menu. According to MakeUseOf, disabling the iGPU freed about 1GB of RAM on a 16GB system, making Windows 11 feel much smoother. Remember that if you disable the iGPU, your PC will not display video without the discrete graphics card installed and working.
Verify the Gain and Combine with Other RAM Tweaks
After saving BIOS changes and rebooting, open Task Manager again and check the Memory section to see the new usable RAM value. If you previously saw 12.9GB accessible from 16GB, you should now see a higher figure, reflecting the reclaimed RAM. You may notice quicker app launches, fewer slowdowns when switching between browser tabs and games, and less frequent stuttering in memory-hungry tools. This change is safest and most helpful for users with 8GB or 16GB who rely entirely on a discrete GPU for gaming, editing, or 3D work. Some memory will still be reserved for devices and GPU driver shared memory, which cannot be disabled. For extra gains, pair this BIOS optimization with debloating Windows by disabling unneeded services and using tools like Microsoft’s RAMMap to clear cached memory during long sessions.