Nvidia GTX 870m (6Gb) vs Radeon R9 m290x (4GB): Which is better for gaming

[NunOnABike]

Hi guys, I am thinking of buying a new gaming laptop as I can't really buy a PC right now. I am bend towards buying a Sager NP8268-S from gentechpc or xoticpc (depends on best international shipping and customer service) with 4th gen i7-48100. I have two options right now for graphics card: GTX 870m (6GB) or Radeon R9 m290x (4GB). I have searched the net for the best performance in gaming and I am getting mixed reviews and responses for each. Notebook review says that R9 m290x is slightly better but some say that it not giving that better performance in gaming. GTX 870m has better core speed but is 192 Bits of memory bus width. So now please give me a simple answer to what should I buy for better gaming overall.
Thank You

 

[biflash]

In laptops i would go for nvidia, they run cooler and give less problems, have more suport.
If your going to do heavy work on cad programs i would recomend the amd instead, much better, if not the nvidea is the way to go.

 

[core 2 duo dude]

i agree, but the 870m has 3GB gddr5, is this an SLI setup then?

 

[NunOnABike]

i agree, but the 870m has 3GB gddr5, is this an SLI setup then?

No this is not an SLI setup....Nvidia has released a different variants in their GTX mobile graphics cards, basically doubling their stock Vram. This is probably a marketing trick as you would never need more than 4gb for gaming and 4k setting but what the hell, I can currently afford it!

 

[wisp1a]

Nvidia use's the Intel shared memory to top it up, like a SLI system it use's intel GPU when its doing normal GFX loads
then when you hit an intense game or computing it use's the 870M.

Its not possible to use the CUDA though as intel chip is on it doesn't find it. Something to do with a deal Nvidia and intel made to bring out more Nvidia/Intel systems

I just sent an 870M back, not because it was not good but the system it was in was not the best, bottleneck by the HDDs.

Its run games like fifa 14 in full HD without and lagging