No issues at the moment but i did not use it extensively yet will update once i do since the build i did not use it a lot yet aside from time consuming software updates/drivers/patches and so on on each platform, only thing i had to mod my case a bit to fit the GPU (small piece had to be cut out of a hdd tray panel with a multi tool)
I looked at R9 290x as well but won't work with xp which was a bummer, Titan X is too expensive for this build, but the 7970 will do just fine it is equivalent to +-R9 280x/GTX 960 my use case for this system is to have games on each of the OS'es from their respective era.