Windows 7 only sees 4gb on msi r9 390 8gb gaming

Solution
I assume you were using System Info/MSINFO to check the cards VRAM? Last I checked, that tool is still 32bit based and wont report any card over 2GB VRAM correctly.

For Windows 7, make sure you run DXDIAG in 64bit
I assume you were using System Info/MSINFO to check the cards VRAM? Last I checked, that tool is still 32bit based and wont report any card over 2GB VRAM correctly.

For Windows 7, make sure you run DXDIAG in 64bit
 
Solution