2016 MB Pro decision- Need advice

[Sully]

The dGPU are new, not much concrete numbers yet, but while the iGPU have advanced, they're still pretty far behind NVIDIA and AMD. There's also the matter of 2 or 4GB of dedicated DDR5 RAM for the GPU. That's a very big deal, both in various graphical tasks, as well as effectively adding 4GB of RAM to your MBP for graphical operations. The iGPU are still using 1.5GB shared memory with RAM, the same as several previous generation of Macs. Minimal differences would be around the neighborhood of double, so there is a very significant difference in capabilities.

https://support.apple.com/en-us/HT204349

Purely conjecture until there are a lot of solid numbers, but the dGPU should be running 200-400% compared to the Iris 550.

So, if the Iris dynamically allocates 1.5 gigs of system RAM, the 2 gig AMD wouldn't be a huge step up would it?

 

[monkeydax]

So, if the Iris dynamically allocates 1.5 gigs of system RAM, the 2 gig AMD wouldn't be a huge step up would it?

Yes, simply because it's a dedicated processor that has much more processing capability than the iGPU, not just in terms of how much RAM there is/can be allocated.

 

[duervo]

Wait a week or two for the reviews to come out. That's what I'm doing at the moment. I prefer to make a decision with as much data available as possible, and right now, there's just not enough out there for me to say one way or the other.

However, if I had to choose right now, I'd go with the 15" for the quad-core CPU, and go with 500GB drive and 16GB RAM.

The dGPU concerns me a bit, but then again, out of the three Apple systems I have owned or continue to own, none of them have had any problems with the dGPU in them. The 2011 i7 mini is on 24x7, and the early 2008 15" MBP was on 24x5 for 4 years before it was replaced with my mid 2012 15" i7 with dGPU. Have I pushed my luck? Maybe I'm due for a failure soon.

 

[skids929]

Wait a week or two for the reviews to come out. That's what I'm doing at the moment. I prefer to make a decision with as much data available as possible, and right now, there's just not enough out there for me to say one way or the other.

However, if I had to choose right now, I'd go with the 15" for the quad-core CPU, and go with 500GB drive and 16GB RAM.

The dGPU concerns me a bit, but then again, out of the three Apple systems I have owned or continue to own, none of them have had any problems with the dGPU in them. The 2011 i7 mini is on 24x7, and the early 2008 15" MBP was on 24x5 for 4 years before it was replaced with my mid 2012 15" i7 with dGPU. Have I pushed my luck? Maybe I'm due for a failure soon.

Lets hope its not this generation!

 

[iizmoo]

So, if the Iris dynamically allocates 1.5 gigs of system RAM, the 2 gig AMD wouldn't be a huge step up would it?

Well, there's a very large number of differences. It warrant the price difference, people whine about MBP being expensive, but you'll notice there isn't a lot of whining about how much more expensive the 15" is over the 13".

First, there's a secondary TDP for the GPU. So think of it as nearly doubling the amount of crunching that can happens with just the iGPU (which the 15" does also have). And the GPU is expressly designed to be very very efficient in how it use power and application of graphics in the way a CPU just isn't.

There's a dedicated pipe between the GPU to it DDR5 RAM. So let say there's an op like you load a 3D building, and then you try to duplicated it 5000 times to build a town, not just the same building, but add things like different paints, shadows, etc.. so that there really need to be 5000 instances of the thing. You can do all that with minimal calls to the GPU, just load the 1 building, and some commands, and the rest is handle between the GPU and it graphic RAM, very little bother to the rest of the system. Using the shared memory, you're using up data pipe in the CPU, and between the CPU and the system RAM, and you've reduced effective RAM for other applications down to 14.5GB.

And let not kid ourself, the GPU has a ton of transitors, supposedly something in the neighborhood of 3B. That thing is quite a feast of engineering.

Now, you add all those and other differences together, and if each thing contribute 10-50% improvements here and there, you'll quickly end up with something easily more than double in performance differences.