need help installing drivers for RADEON VEGA 3

That explains why there's no Win 7 driver at the ASUS website for your system.
Honestly, I'm not knowledgeable enough about the duo boots with different OS's and the use of different drivers to help you. It would seem to me, you would be good if you ran Win 7 in a VM, if you're not. I don't think the "sandbox" is applicable here. All this is better addressed by the big boys like torchwood or maybe even by posting in the Win 10 forum.

torchwood said:

lets cange the defaut then

from regedit
HKEY_CURRENT_CONFIG/System/CurrentControlSet/Control/VIDEO.

change your x and y default values, screenshot shows my defaults as 1368 768

Double-click the "DefaultSettings.XResolution" heading, and select the "Decimal" radio button in the dialog box. Type the horizontal resolution of your choice in the "Value data:" text box; for example, "1152" (without quotes) to set a width resolution of 1152 screen pixels.

same for y axisAttachment 420827

tried that, it stayed the same
also when i ran the windows memory test thing, it was in a bigger resolution.
one more thing instead of saying generic pnp monitor or something it just says "(Default monitor) on"