According to what Microsoft has publicly stated in their last couple of press releases, all Win10 Tech Previews and the Win10 RTM version due in July of this year will use drivers from chip manufacturers such as AMD, NVIDIA, and Intel that will be compliant with Win8.1 WHQL drivers as submitted to Microsoft by the manufacturers of these devices. However, after 1 year or so (probably less), and the backlog of submitted chips and hardware peripheral to the MS WHQL labs backlogs get cleared out, MS has stated they will support Win8.1 drivers. This of course will change, as it did with the advent of Win8, Win7, Vista, XP, 2000, etc. This is nothing new. Video Display chip/card manufacturers are usually at the top of the heap for testing with the new OS for WHQL certification; without that the manufacturer--in this case AMD cannot legally use the Win10 logo on the retail box of any video card with this chip inside of it. From past experience, this is usually less than the stated 1 year; more like a few months after PC, laptop, and tablets begin appearing on retail store shelves at the big box companies (Walmart, Best Buy, Staples, etc.)
Are you planning on installing this card now? If so, what build of Win10 are you planning on installing it on? You can also check the AMD website, as some chip makers are now releasing Beta tests of their Win10 drivers; however, they of course do not guarantee that they will work on production (RTM) release Win10--that's the one that will come out on machines in stores in the Fall of this year. I don't test Gaming apps on hardware/software platforms, there's like 10 million other guys who specialize in doing this and it's a niche market. If you're Gaming, I suggest you hit the Gaming websites, e-zines, or Gamestop to check on this in their community forums too. If you're not Gaming, it would really depend on the types of apps you are planning to run with your newly upgraded Win10 system (Tech Preview only at this point, since Win10 does not yet exist in retail). If you are doing something like AutoCAD; it's unlikely you'll get any help, as they always have lagged historically on getting their drivers to work with the new OS releases of Windows. The best thing to do, is to NOT install the Win10 upgrade on your existing system, but rather use an entirely different computer to do your testing. This is how I do it. If you cannot do this for cost or other reasons, at least switch out your hard drive, and purchase a 2nd hard drive for the Win10 install. If it fails, you can just swap out your original hard drive and be back up and running on Win8.1 in a few minutes. I use 4 different hard drives for the various builds (versions) of Win10 that come out on a near weekly basis for testing.
Let us know what your are planning to do, and we can advise you further.
There are also some sticky licensing issues we still don't know about Win10 and it could turn out to be a very expensive proposition to keep it on your existing PC.
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