Solved Surface Pro 4 i7 throttling question

[Scott Wells]

Sorry if this seems like beating a dead horse, but I have searched and haven't quite found the answer to my question.

I currently have a Surface Pro 3 i5 8GB/256GB and have generally enjoyed it, but the thermal throttling issues have definitely marred the experience. I don't use it for gaming, but I do use it for Java development. After developing for a while thermal throttling kicks in big time and makes continued work pretty painful. I've tried the whole USB fan thing which helps some, but it's VERY noisy and frankly pretty disappointing that it's even needed.

I'm considering purchasing a Surface Pro 4 i7 16GB/512GB as an upgrade/replacement. I already have the docking station and SP4 type cover, so I'm relatively invested in this platform, plus I really like the form factor. Before I pull the trigger, I'm trying to figure out if I'm just going to have the same experience with the SP4 i7.

I've seen some descriptions of how throttling in the SP4 differs from thermal throttling in the SP3 i5/i7, but I wanted to ask others who have used the both the SP3 and SP4 for relatively heavy business-oriented tasks (as opposed to gaming), are the major drops in productivity due to throttling addressed or are they still present and frustrating?

Thanks in advance!

 

[quadxeon]

Can't tell about a difference between SP3 and SP4, but I can tell you that the SP4 is doing very well for my 3D animation / simulation work.

Both, the i5 and now my second SP4, the i7 are great. Longest computation task I ran so far took two hours at permanent 100% CPU. Minimal throttle, the i5 went from 2.85 to 2.7, the i7 from 3.2 to 2.8 .
I'm experimenting with Intel's XTU, since two days. Lowered the Vcore by 95mV - no throttle after one hour at 100% CPU.

CPU performance wise, both are very close together, not sure if I would buy another i7, the i5 is already very fast. (not talking about gaming here)

I reckon that the SP4's biggest "problem" is the operating system, at least at the moment.

 

[Scott Wells]

Thanks! That's very helpful. I was just trying to decide whether to get the SP4 i5 8GB 256GB or the SP4 i7 (either config) given that when it's not throttling, my SP3 i5 8GB 256GB works very well. That would save me a decent chunk of $$$ if the net effect is a much more consistently-performing version of what I have. My guess is that 3D animation work is going to be more computationally taxing than the development work I'm doing, so that's a pretty solid data point. Thanks again!

 

[masterpace]

Based on my experience, the SP3 i5 thermal throttling is severe, both on the CPU and GPU side. The SP4 i7 on the other hand both suffers from power throttling and thermal throttling although it's much less critical than on the SP3. I've observed power throttling using the 35 W adapter, but haven't seen it by using the 65 W one. Power throttling happens with the 35 W adapter, 'cause it doesn't supply enough power for the whole package (tablet) whenever the i7 is running as a sustained loaded (greater than 15 W). Thermal throttling kicks in whenever the back case sensor crosses a certain temperature treshold. I've done some gaming sessions. By plugging a USB fan and pointing it straight at the back of the SP4, I can easily increase my framerates by 20 % (I guess the sustained TDP using a fan is a bit higher in that case). For instance, I get about 2200 3DMarks 11 without a fan and easily 2500 - 2550 /DMarks using a fan. Of course, in both scenarios, I'm using a 65 W adapter (to avoid power throttling).

 

[Scott Wells]

Thanks for the info. I pulled the trigger on an SP4 i5 8GB 256GB (basically the SP4 version of the SP3 that I have). I'm going to run it through the paces for a couple of weeks after I get it, basically hammering it the same way I use the SP3 today that results in severe throttling. Hopefully the issue will be resolved for all practical purposes. If not I may bail on the SP line altogether and grab an ultrabook for this purpose. I'll be happy to post my findings here if anyone is interested.

 

[ndiguy5]

Glad I haven't upgraded. Plan on keeping my SP2 until it no longer works.

 

[Scott Wells]

Okay, I've had the SP4 for a week or so now and have been using it heavily. It's a HUGE improvement over the SP3! It's not 100% perfect, but it's much closer to what I wanted/expected when I first bought the SP3.

Under heavy load (repeated command-line and IDE builds of a decent-sized Java project), the fan eventually spins up loudly, but unlike the SP3, it doesn't seem to throttle the CPU much if at all. Build times are finally quite stable across long sessions.

Because of the higher resolution internal display, the default scaling factor is 200% vs. 150%. This seems to help quite a bit when docking and undocking, presumably because the scaling factors are whole number multipliers of one another (100% when docked w/external monitor vs. 200% when undocked w/internal display). I'm not finding that I have to sign out and back in very often at all now to avoid blurry rendering.

The third item that had been driving me crazy is less about the SP3 vs. the SP4 and more about having taken a step back to resolve long-standing issues. My main display is a 2560x1440 27" LCD with DVI and HDMI inputs. I'd picked up a cheap mini displayport-to-HDMI adapter which worked, but wasn't without issues. The maximum stable refresh rate for the full resolution was 40Hz, and I've had to turn off the monitor when not using it or it would audibly click off and on searching for a signal. I picked up a $20 active mini displayport-to-HDMI adapter which resolved both of these issues. I now get a rock solid connection at full resolution in 60Hz, and the monitor reacts 100% properly to the various states.

At this point I'm a very happy camper! I managed to get the SP4 i5 8GB/256GB for about $1.1K by taking advantage of the President's Day $100 discount on top of an educational discount through my kids' school. I'm either going to sell the SP3 or, if my wife decides she wants it, do a clean Win 10 reinstall and set it back up for her.

I hope this helps anyone else who is trying to decide whether the SP4 addresses some of the shortcomings of the SP3. I'm happy to answer any additional questions you might have as well...