Surface Pro 2 CPU States

[daleuk]

OK, please stick with me as I'm new on here but I'm loving the Surface Pro 2 but I have a question with regards to the processor and how it behaves.

The current power plan is set to Balanced with the Minimum Processor State set to 5% and the Maximum Processor State set to 100% - I must also say the Surface is plugged into mains power.

I play Minecraft a lot and noticed I was getting poor FPS 30FPS whilst playing it, I opened up task manager and noticed the CPU usage was at about 1ghz, no matter how choppy the frame rate, or how the PC was struggling it would not go up. Everything on the balanced power settings I have set for max performance when plugged in.

Subsequently I changed the min processor state to min 100% / max 100% and the CPU indicated in task manager 2.4GHz. I ran Minecraft again and it ran perfectly and noticeably faster at a steady 60fps on high settings, although the fans came on but didn't get too hot. It also worked really well (2.4GHz) on Maximum Performance setting even with the Min set back to 5%, it still ran at full speed.

So my questions:

1. Why does the CPU not speed up to 2.4ghz in balanced if the program is obviously demanding and getting poor FPS, especially as it was set to 5% min / 100%, does the software have to specifically request the turbo boost or is it automatic.

2. Does it do any harm (apart from getting hot) leaving it at 100% minimum speed?

Can someone with a lot more knowledge please explain this or even how the min/max processor states work as well as how the turbo boost works. Surely if its set to allow the processor to go to maximum 100% it should do exactly that, not hover at about 50% speed?

I appreciate all your advice,

Many thanks.

 

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Why does the CPU not speed up to 2.4ghz in balanced if the program is obviously demanding and getting poor FPS, especially as it was set to 5% min / 100%, does the software have to specifically request the turbo boost or is it automatic.

Only an Intel engineer can answer you that question properly.
But mobile processor power management is a bit more aggressive. I think that either: Minesweeper uses CPU clock to execute instructions (in other words, poorly designed. I mean it's already a Java game, so that's not a good start), or that the performance requires from Minesweeper is not enough for the CPU to go faster.
If you are patient, this summer, it is planned for me to developed a software that will change the Windows power plan profiles base don if you are plugged in, or not, and which program you run, using a community supported catalog of software and applications (the idea is to reduce the need to add games and program on it, and that once it's added, you don't need to add it again, even if you format and re-installed, as the catalog will be shared with everyone).

However, I can't provide any promises. I really want to do it, but I don't know my plans for summer.

2. Does it do any harm (apart from getting hot) leaving it at 100% minimum speed?

Yes. The device will get warmer, which will make the fan kick in more frequently which will reduce the battery life of the device. In addition, heat is not good for lithium-ion/poly batteries, which accelerates the aging process. In addition, you increase teh chances of the system throttling. This is a common situation where people notice greater performance using Balance than High Performance on many mobile computers, especially the small and compact ones, after a while in operation. However, I have not done any testing on Surface Pro 2.

Can someone with a lot more knowledge please explain this or even how the min/max processor states work as well as how the turbo boost works. Surely if its set to allow the processor to go to maximum 100% it should do exactly that, not hover at about 50% speed?

Here is a great article on how it all works: AnandTech | Dynamic Power Management: A Quantitative Approach

The percentage value that you put, is not a direct relation of the speed of the CPU. The CPU support several frequency and voltage profiles, and the percentage value that you put, will pick the profile closest to it. TurboBoost is a technology witch overclock the CPU up to the max speed designed by the CPU. This overclock is tested and approved by Intel, and designed by the CPU to not cause any damages. And we all know Intel rigorous testing and high standards. When does it kick in? It kicks in, if the CPU judges that the system is cool enough to allow it. That is why on poorly designed laptop where the system cooling is inadequate, the processor can't reach anything close to the max TurboBoost speed. In the case of the Surface Pro 2, assuming you have the 4300U CPU, and based on Intel TurboBoost Monitor Utility, the CPU will go up to 2.8GHz most of the time, with rare peeks at 2.9GHz. This is very good. At worst, (device is warm in a warm room), it will be, based on my observation (everything I mentioned are my observations), is ~2.6GHz, which is excellent. This means that when you need performance, you'll get some nice power at 2.6GHz at worst conditions. Well... "worst" conditions. I haven't put the Surface Pro 2 in an oven and check, nor used a CPU stress test, as I see these scenarios not real world ones. It is an ultrabook in a tablet body, not a desktop.

 

[NeoGrandizer]

Even kicking at 100% processor, I wouldn't want that. I much prefer speed stepping. On top of it heating up, the vcore voltage being fed to the CPU will ramp up to keep the clocks stable. This causes the heat and in turn can shorten the CPU life if not careful about it. I know mine spiked to a constant 2.9GHz a few times during my setup and install of programs. I was worried because it was getting warm-hot and battery life was being chewed up. I still haven't installed AIDA, CPU-Z, etc to check things out component wise. Will probably do that on the weekend.

 

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This causes the heat and in turn can shorten the CPU life if not careful about it.

Not really. You would replace the Surface Pro 2 way before its any issues, after giving it a second life by passing it down. It will pass 6 years easy. Other components might break before that.
The reason for this, is that your are not overclocking the processor. It was designed to operate at higher voltage. But more heat, yes.

know mine spiked to a constant 2.9GHz a few times during my setup and install of programs. I was worried because it was getting warm-hot and battery life was being chewed up. I still haven't installed AIDA, CPU-Z, etc to check things out component wise. Will probably do that on the weekend.

When on battery, you should use Power Saver power plan to maximize battery life. In my case, I set the min and max CPU for power saver to 0-30% forcing it at minimum clock, to maximize battery life. But that is because I am used to close program they'll shortly need afterwards, like my web browser. Bad habit.

 

[NeoGrandizer]

Thanks for the tip.

This is my first Windows tablet. Owned a notebook once, but a long time ago. Mostly worked off a desktop and Wacom tablet. Using this mostly as an art tablet with Painter 12, Sketchbook pro, Adobe Photo Elements, etc.