Can someone with a bit of knowledge just clarify one thing for me:
If rMBP 13 goes to quad core, will that also effect the Iris graphics? I mean, aren't the graphics just a function of the CPU now? So would quad core add 50% or so to frame rates?
If that is the case, quad core could be a major boost, given that broadwell is looking like offering something in the range of 40% gains just on architecture alone.
1) nobody knows if 13-inch rMBP will get quad-core. It's pure speculation.
The way it works with Haswell, and most likely broadwell is as well, is that quad-core can get the iris pro. Iris pro is better graphics than those in dual-core(rMBP 13 Haswell).
2) Ad 50% to framerates? That depends on the game you want to play. Some games are bound by CPU mostly, some by GPU. A game like Total War or Guild Wars 2 is very dependant on a fast CPU, because they cover many characters, large areas. That taxes the CPU so these types of games benefit greatly from quad-core. Twice the number of actual cores is a massive performance boost.
Some games are GPU bound. Like Crysis. Games like these have high level of effects like advanced shaders, normal mapping, real time shadow, advanced forms of blur and so on. These types of things taxes the GPU.
Some games are heavily dependent on both CPU and GPU. Games like Battlefield 4 taxes both the CPU and the GPU thanks to a big scope(big world, lots of characters and geometry) as well as advanced graphics technologies.
So it's impossible to say how much it would improve if 13 inch rMBP goes to quad-core and possible iris pro graphics. If heating would be an issue they would might have to clock the quad-core a lot lower than their dual core counterpart, and then performance becomes up to if the individual games takes advantage of more than two CPU cores, or it mainly takes use of two cores with a lot of MHz. So it depends on the game.
We don't know how much the next gen graphics from Intel will improve, but 20-40% are the targets I've heard. So rule of thumb is expecting something in between that. 25-35% increase. Perhaps for Iris, perhaps for Iris Pro. perhaps for both.
But I will repeat myself again: If gaming is important to you. If a significant reason for buying this machine is gaming. Then please. Please get the one with the dedicated graphics.
Light gaming is fine on the 13-inch haswell. It's completely fine, but light gaming also means you can't expect to be get mad when a game you wanna play don't really run because it was not optimized for integrated graphics.
It's about drivers, dedicated vram and many computer games being decided to run on dedicated graphics cards. The 15-inch with 750m is expensive, but if you really wanna game a lot. Then I really think you should go for that. The next line up of games like Titanfall, GTA5 PC and Watch_Dogs are going to require a lot of Vram I think. And a fast quad.
