Adjusting the size of GPU VGA Shared Memory (also known as VRAM) may directly affect the graphics processing and gaming performance of your PC. VRAM is the storage on the graphics card that holds image and video data. When the VRAM is insufficient, the PC will be forced to fetch data from system RAM, leading to decreased performance in gaming and image processing.

If your PC is slow due to insufficient VRAM, you can try adjusting the VRAM size to enhance graphics performance. Different PCs and graphics cards require different VRAM adjusting methods. With that said, users are often able to select VRAM size in BIOS settings.         

Please note that adjusting the VRAM to an excessively large value may reduce the stability of the system, or cause frame rate drops. Before adjusting the value, make sure you understand the performance and the limitation of your PC.

Steps:

1. Shut down the PC completely, and then press the power button. When the logo appears on the screen, press the Del key quickly to enter BIOS settings.

2. After entering BIOS, use the arrow key to enter the [Advanced] setting and select [AMD CBS]. 

3. Enter the [NBIO Common Options] setting.

4. Enter the [GFX Configuration] setting.

5. In [UMA Frame buffer Size], you can select the VRAM size according to your needs.

Allocate VRAM automatically:

[iGPU Configuration ]: Auto

[UMA Version]: Auto

[GPU Host Translation Cache]: Auto

[TCON INSTANT ON LOGO]: Auto

The following screenshot indicates that the VRAM is allocated automatically.

Customize the VRAM size:

[iGPU Configuration]: UMA_SPECIFIED

[UMA Version]: Auto

[UMA Frame buffer Size]: The default value is 4G, but you can select other values according to your needs.

[GPU Host Translation Cache]: Auto

[TCON INSTANT ON LOGO]: Auto

The following indicates that the VRAM size is set to 4G.

6. Press [F4] and select [Yes] to save configuration and exit.