I have both at the moment - the base 2.2 Iris Pro and the 2.8 with the 750m. Decided to stick with the base model and return the 2.8. I never play games or do hefty video work so the Iris Pro is fine. The 2.8 runs hotter and the fans are more noticeable. Geekbenched them both - 13100 v 14500, which is actually pretty good for the 2.2. The only downside is the smaller SSD - but I'll get one of those 128GB SD cards from Transcend to open it up a bit until third-party options appear. I guess the point I am making is the base model is pretty fab value for what you get and what you pay - and certainly none too shabby when run alongside the top end model.
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15" 2014 2.2 vs 2.8
- Thread starter grame
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It is a factor, but the Megahertz wars are over and at this point Intel is increasing performance in other ways. bumping up the speed from 2.2 to 2.4 will give you a small boost, but I don't think in real world activities it will be that noticeable.
Probably because if you did that, the CPU would run much hotter and under stress it would probably get so hot it'd practically selfdestruct.
Sure, higher clocks do give it a bit more performance, but it's not as drastic as the relative clock frequency increase would indicate. There's a lot of other factors that make up the performance of the CPU and not all of them are affected by the clock frequency going up.
I don't think a few hundred MHz does add much, or any, heat. Intel CPU's generally have quite a lot of frequency moving room before you need to start upping the voltage. Having this kind of moving room is the reason why a lot of PC enthusiasts used to lower the voltage on their CPU's to get lower temperatures and power consumption without losing any performance. The identical TDP (which is basically the heat production under maximum stress) figures would indicate that the two CPU's run at the same voltage.
With 4 GHz, they would obviously have to significantly up the voltage and this would also increase the heat produced across the board.
In heavy tasks, such as Macoh stress tests, the 750M model actually runs cooler.
This is because tasks are spread over two chips instead of just a single chip.
In the Macoh stress tests, the Iris Pro model experienced throttling shortly into the test. The 750M variant did not throttle at all and ran cooler.
The myth that the dGPU model runs hotter has to die. The dGPU can be disabled with gfxcardstatus.
This is because tasks are spread over two chips instead of just a single chip.
In the Macoh stress tests, the Iris Pro model experienced throttling shortly into the test. The 750M variant did not throttle at all and ran cooler.
The myth that the dGPU model runs hotter has to die. The dGPU can be disabled with gfxcardstatus.