Very bad: Vega 64 Cryptonight V7
It looks like you are using default config.txt
Cast XMR automatically configures for you. For SRB, you need to change the intensity, worksize, and thread number until you find the ideal one.
Changed but not good

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What intensity are you using? Here is a pic with I:119,8 W:16 dual threads:

... looks good to me
Your can share PowerPlay Registry For Vega 64

. and config, full OverDriveNTool config Please share
Thanks
Ppl normal 900 for all cards on my asus and liquid i use the sock unlock one.
i think you only have to use my config and you are fine :
{
/* Type can be : normal, normalv7, lite, litev7, heavy, ipbc */
"cryptonight_type" : "heavy",
/* Intensity 0-> auto intensity, or value from 1-300 */
"intensity" : 60,
/* To use 2 threads per card set double_threads to true */
"double_threads" : true,
/* Uncomment this if you want to set GPU target temperature */
/*"target_temperature" : 0,*/
/* Uncomment this if you want to set system shutdown temperature */
"shutdown_temperature" : 90,
/* Uncomment this if you don't want to use the built in watchdog, but you want a script to run on GPU fail */
/* If you use the reboot-windows.bat it will restart your computer if a GPU fail occurs */
"reboot_script" : "reboot-windows.bat",
/* Advanced settings for each GPU manually */
/* Put in devices that you want to use, if you for ex. don't want to use gpu 2, just don't insert it,like in this example */
/* Id starts from 0 , not from 1 !! */
/* To get a list of available devices with their id's, use --listdevices parameter */
/* This is just an example, edit it and remove comment lines !! */
/*"gpu_conf" :
[
]*/
}
** if you want to use Cryptonight V7 just use 120