"There is still no visible graphic display. Would it make any difference if I uninstalled realtek and then reinstalled it? "
- The EQ is part of the Realtek HD Audio Manager software that is bundled with the driver.
If there is no Realtek HD Audio Manager listed in
Windows Control Panel, and it's not available in the Taskbar settings
(R\click on Taskbar. Click on Taskbar Settings > Click on
Select Which Icons Appear on the Taskbar ),
reinstalling the driver may help.
- Use only the driver from the mfg of your motherboard
(or machine if laptop).
Uninstall via Programs and Features and reboot before reinstalling the Realtek drivers.
"it doesn't support the high definition driver"
I believe Realtek have called their driver HD for many years, and those drivers have (maybe not with the latest motherboards)
also supported the earlier AC'97 front panel option (they are not much different).
You left no clue how recent your machine is, but if there is no dedicated Win10 driver available for your machine from the mfg,
and the problem started after a version or cumulative update you may have hit the end of the road regarding full Win10 compatibility,
which may be limiting the Realtek driver\software functions ?
.