Some older games or applications check for a minimum VRAM amount (like 512MB) and will refuse to launch if it's lower, even if your system could technically handle it. You can "trick" Windows into reporting a higher value.
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To ensure your GPU is running optimally, keep your drivers up to date:
Boot from the USB drive. During installation, you may see a warning: "This PC can't run Windows 10 due to graphics incompatibility."
If you have Intel HD Graphics or AMD APU with 512MB “dedicated” VRAM (actually shared), you can force more.