In the BIOS, click on 'Advanced' and the 5th setting from the top should read 'PCIe Resizable Base Address Register'.  Then you can verify that it's on in the NVIDIA Control Panel under Help | System Information.

Forgot to mention that you'll need to update your VBIOS too.

https://www.dell.com/community/Alienware-Desktops/RTX-3090-3080-3070-3060-Ti-VBIOS/m-p/7894486 

Hi,

thanks for your help.

I was able to activate the resizable bar on the BIOS option.

Thanks again

How to check if correct VBIOS is present on system?

Use GPU-Z: GPU-Z 

Then ensure you have the latest video card drivers, have resizable bar enabled in your motherboard BIOS. If all goes well it should say resizable bar is enabled in the appropriate box.

Is the latest version available under this link? 

Wow ! I thought Resizable Bar didn’t work for the R11’s and rtx cards. Something must have changed that I didn’t pay attention too. I think I have the vbios 2 version.