Brand New r17 5737 cant get amd gpu to work

So i bought this notebook yesterday.
i7
8gb Ram
Amd hd 8870M 2gb (also has integrated intel hd4400)

It came with linux so first thing i did was format and install windows 7 x64.
After that i installed all newest drivers from amd and intel (because i didnt know i should try dell's drivers) .

After installing everything, device manager recognised both gpu and everything seemed fine, but whenever i launched an application that has the ccc switch settings set to High Performance, the screen goes black and i have to restart(sound still playing though, but without mouse cursor showing)

So i searched a bit and many ppl on forums had same problems so i format again, fresh install of win7 to try the dell's drivers. Installed everything again but the problem was still the same. 2 seconds after game launch=black screen crash.
By the way its not an application specific problem because i even put Firefox as "High Performance" with power settings set also to "high performance" running on AC, and it still crashed.

So i researched some more and i verified bios A06. dell drivers A00 for both gpus.
someone also suggested installing amd's drivers 13.9 ON TOP of those A00. That actually got the game to run for 2 seconds instead of one. froze and then remained frozen for 10 seconds before black screen appeared. so it was just a delay.

Atm, as i m waiting for a response here i m installing windows 8.1 hoping for better drivers.

So i have 2 questions
1. why did the downloaded bios suggested by dell(put my service tag and everything. no mistakes were made i m 100%. triple-checked) were A06 when there was a A07 bios installed to begin with(like from the store). i followed dell site and downgraded anyways, but didnt make any difference in my problem. i think its intresting but irrelevant
2 and most important.
Do you think i can try something else or should i just go claim DOA from the store because of bad amd gpu?how likely do you guys think it is for the gpu to be bad.

Thanks to anyone taking the time to read this

PS forgot to mention. one of my later attemts was when i had dells A00 drivers on. then put on amds 13.9(without removing previous). so when that failed i tried to use amd uninstall utility. when that finished and promted a restart, my mouse deactivated and i had to confirm restart with keyboard. After the restart got constant blue screen as windows logo began to appear on start. fixed it with windows restore, did everything again and got same blue screen at the end. sonow i m formating to get win 8.1 on