Just an update, for those who didn’t notice. The new Skylake CPU are here, including the mobile versions, and the mobile I5 Skylake CPU is unlike the previous generations of Broadwell and Haswell I5s. The Broadwell and Haswell (and before) I5 mobile CPU were 2C/4T CPUs, meaning they had 2 ‘real’ cores + 2 Hyperthreading cores, making a four logical cores. The new Skylake mobile I5 CPU is a 4C/4T CPU, meaning, it has 4 ‘real’ cores and no Hyperthreading cores.
In practice, the mobile Skylake I5 has a lot more computing power than the Broadwell/Haswell I5s. It doesn’t mean it will show in games right away, but for 3D in general and for some games, plus future DX12/Vulkan games, it should be beneficial to some degree, at least with a very high performance GPU.
Let’s check a comparison of a Haswell I5-4210H, Haswell I7-4720HQ and a Skylake I5-6300HQ:
- I5-6300HQ, 4C/4T, 2.3-3.2GHZ, around 2.9GHZ under full load
- I5-4210H, 2C/4T, 2.9-3.5GHZ, around 3.3-3.4GHZ under gaming load like Crysis 3 (as tested here)
- I7-4720HQ, 4C/8T, 2.6-3.6GHZ, around 3.1GHZ under gaming load. Numbers and info are taken from here and here
What are we seeing?
- Some games see a good advantage of 10% going from an I5-4210H to I5-6300HQ, and that’s without an advantage in core clocks, mind you.
- These games are mostly Metro LL and Civilization Beyond Earth from this list, which have not seen major updates really. However, drivers have changed and they might be part of the advantage in newer benchmarks I did with the Alienware 15 R2.
We already know that Skylake CPUs have an advantage over Haswell CPUs clock for clock in IPC of around 3-6% according to AT tests (here), but I don’t think this is the main issue here, as these games are not CPU-bound but GPU-bound and although the architecture advantage can add to FPSs even in a GPU-bound game, since we see no advantage in some games like BF4, we can assume that’s not really the major factor here. Add to that the fact that the I7 Haswell numbers are very close to the I5 Skylake.
The conclusion is that the Skylake I5 vs Haswell I5 advantage in these games probably comes mostly for the 4 real cores of Skylake opposed to the 2C/4T of Haswell. Again, it doesn’t necessarily the reason, because there are other factors, even the variance in the games’ built-in benchmark results and updates to the drivers and games, but if there is an advantage for newer games, that’s probably it.
Moreover, the 4C/4T will be useful with high energy eGPUs in the future. I’m saying that because purchasing a laptop with a Skylake I5 might be a smart move for the future as a gamer, given you can connect an eGPU (like in the Alienware 15 R2 case).
The Arstechnica tests with GTX 980 and a Radeon 290X, two very powerful GPUs, even in DX12 (remember, much better utilization of multiple cores, as the marketing goes), showed no advantage over 4 cores.