Which laptop GPU can match an HD6990M?

[Jiniix]

Hi CF

As the title states, I'd like some opinions on which laptop card that can match the HD 6990M in performance - preferably from the newest generations

My old, now my brothers, laptop has had its 6990M die a few times, and now the shop doesn't have any more in stock. So they offered me a new laptop as replacement, but they can't give me any laptops with anything better than a GTX 950M.
I mean, it's the same chip as the HD 6870 with GDDR5 2GB 256-bit, 1120 stream processors and core/RAM: 715MHz/900MHz.
The GTX 950M is GDDR3/5 (both versions exist) 2GB 128-bit, 640 CUDA cores and 1097MHz/5000MHz.
MHz is obviously incomparable, but you can see why I'm skeptical I hope.
Monitor is 1080p on both solutions.

So yeah, what's the lowest GPU I should aim for?
Performance is everything, and 'features' such as Optimus or Enduro are actually a big negative in my book, though sadly pretty much unavoidable today.

Edit: Just got off the phone with them, it's an GTX 850M they can offer.

 

[Darren]

This is what I use for comparing laptop GPU's.

http://www.notebookcheck.net/Comparison-of-Laptop-Graphics-Cards.130.0.html

 

[Jiniix]

Yeah I was looking at that too.
I'm trading:
i7-2630QM, 2x4GB 1600MHz, 500GB SSHD, HD 6990M, 1080p TN (I believe it's TN) @ around 3.6kg (guesstimate)
to:
i7-4700MQ, 2x4GB 1600MHz, Crucial BX100 250GB SSD, GTX 850, 1080p IPS @ ~2kg

I think it's a good trade regardless, as my brother is still in school. He also likes to edit videos, so maybe he can utilize the CUDA cores to something.
Both are Clevo designs, which I'm a huge fan of. They initially offered me a Lenovo, which I promptly turned down nicely