You can use something like rivatuner to cap your FPS at your refresh rate (or lower, usually after 80 you won't see a difference in most games). Then if your not using sync it won't be processing unnecessary frames and making loads of heat/noise. Doing this can stop coil whine too.
FYI For years AMD has cap limiter on the driver settings
I have a Gigabyte Radeon RX VEGA 64 WindForce OC 8GB HBM2 PCI-Express Graphics Card playing on a MSI Optix G24C 24" 1920x1080 VA FREESYNC 144Hz 1ms Curved Widescreen Gaming Monitor.
I don't run any kind of Vsync, or freesync. For some reason freesync causes fluctuating brightness.
My graphics card absolutely takes off in some games, and gives me some nasty coil whine, especially in menus etc.
I thought I'd use the radeon software to limit my FPS to 144. But I've read that I should actual limit it to 90.
Shouldn't I be aiming for the limit of my refresh rate?
a) The Freesync flickering has nothing to do with AMD or the GPU. Pay a visit to the MSI forums, is ongoing issue since 2017 and MSI reply to all threads is "we doing testing".
b) your monitor support freesync ranges
Display Port: 48~144Hz
HDMI: 48~120Hz
c) Do you use a DP1.2a or better DP1.4 rated cable? The one with the monitor is DP1.1. (MSI and all companies are cheap here)
Have you tried to use HDMI (2.0b preferably) cable?
If not buy a DP1.4 RATED cable, they are not that expensive but they are perfect, like the Club3D CAC-2067 1.4/HBR3
d) To set cap limit NEVER EVER use Vsyc or 3rd party software on AMD cards. The drivers have the option to do so, not only for all general settings but per game profile also.
e) Make sure your monitor is set at 144hz (or 120hz on HDMI) at windows, since W10 has the tendency every so often on major upgrade to reset to 60hz.
Let us know how it goes.
For coil whine pay a visit at V64 owners thread for undervolting settings. They will improve performance, and reduce coil whine and power consumption.