950M with GDDR3

I am looking at the Sager NP6659 which comes with a 950M with GDDR3 memory according every Sager reseller site.

After doing some research, I have only been able to find two variants of the 950M. One that comes with GDDR5 and one with DDR3. I know the DDR3 is going to be much slower than the GDDR5, but where would the GDDR3 fall in line? I can't find anything on it.

950M with GDDR3