I am using the 20210831 version and it is working safely at 120hz.
The sub monitor is being used, but only the main screen is displayed and the Valkyrie's monitor is not displayed.
I tried changing the sub monitor to the main monitor, but sdvx works on the main monitor.
When running spice64, programs corresponding to the main monitor and sub-monitor should be running, but only the main program continues to run.
Thanks a lot for your help.