Dell Inspiron 3910 Graphics Downloading Slow

I need some help/ideas with what I may be overlooking in my diagnosis of a problem.

I purchased the following in September, 2022.

• Dell Inspiron 3910 with Intel Core i7-12700 
• 64 GB of Memory.
• 512 GB SDD & 2 TB HDD
• NVIDIA GeForce GTX 1660 Super 6GB Graphics
• I run two 24"monitors, an older Asus (HDMI) and a newer HP (Display Port).  Both displays say they are connected to the Intel UHD Graphics 770.  I thought this may the problem but then read online this is correct.
• Only usage is my PC, my wife's tablet, and streaming TV..

PROBLEM:

It has worked perfectly until a recently when any graphics/video I try to download either takes an awful long time or times out.  Simple examples would be any webpage with a picture in it such as Face Book messenger, Youtube, banking home page, etc..  Photos & videos from SDD/HDD load and run fine so I don't suspect the graphics card.  All text seems to download as fast as it always has.

SUSPECTS: 

Internet, modem, & router -

     Confirmed with internet provider (Comcast) everything was working correctly from their end.

     Ran several speed tests averaging 200 Mbps download.

Virus, malware, or some other invasive s/w.

     Ran a full virus scan using Avast, no problems found.  Windows says all my drivers are up to date but Avast disagrees & suggests I purchase an add-on to their antivirus which I have not done yet.  ( Cleanup Premium & Driver Updater)

I am now suspecting my antivirus's firewall but have not figured out yet how to disable it which is probably my next step.  My last step would be to back up all of my data, wipe my hard drive and reload Windows 11 which I don't really want to do until I have eliminated all other suspects.

    ANY additional ideas or thoughts as to what I may investigate and how to resolve would be very much appreciated.