Video R6 M340DX 2GB. All 64-bit windows. On windows 8.1 3gb memory used in 6gb available, and on windows 10 when used 1gb available 4.5gb. Tried driver from windows 8 to windows 10 set is not defined there. Drivers downloaded on the AMD website. But otkatany video driver demolished the first 10 windows is not restored. The first windows 10, it was also like this on windows 8 3gb memory used when 6gb available. At some windows remain, the games are the most productive and qualitative. Maybe it's because of the power saving features built-in card is the graphics card issue or driver on windows 10 windows weaker 8. How can I check in action two cards at the same time I do not know. In GTA V can be run at high performance two cards here Most Wanted ran, well, is not slow, unlike the brakes on an old laptop with 512 MB video card.