Win10TP and switchable HD4k with 5k series

Hello, I've installed Windows10 tech preview and looking for solution on the drivers. My graphics cards in laptop are HD4250 and HD5470. I have to say I used dellon123 drivers for Win8.1, since I had similiar issues but they aren't working yet for Win10. Official uke2: AMD site says for 4000 series I should use bundled drivers. Seems like standard Windows update drivers work for 5470, but not exactly for 4250 and then I can't change resolution, everything is quite laggy.
Anyone found a solution yet or tried 10 preview entering switchable hell?


Ok I got a partial solution which is:
HD5470 using Omega drivers
HD4250 using old catalyst 10.2 driver installed manually by "add legacy hardware"
GPU switch isn't working and movies through SVP are lagging, but normal madVR works ok for video playback. YouTube videos are also smooth. The games I tested were CSGO, WOW, Quake3, SW:Jedi Academy and they work good on same settings I used on Win7 before.