CPU Throttling on 15 inch Surface Book 2 after 1709?

[Bill Dolan]

That was the same thing I was thinking. I talked to them on the phone once today and again on chat and they were both pretty helpless. They gathered information and said they were sending it to engineering and thought it was some sort of software issue. Which I highly doubt it is too. Might call them again to see what they can do.

 

[unruledboy]

13 inch does have:

Surface Book 2 - Does it throttle? - YouTube

 

[Seneleron]

The old fan on the back trick ^^ Actually a good video for baseline data. Granted, the 15" version 8650u is configured differently and has active cooling [plus additional room for passive cooling] But it does give a nice baseline on how MS kinda designed the book 2 and how the chip is configured.

I'm gonna play with XTU today and see how she undervolts. I still say 1.35-1.4v on a ULV chip is insanity, but how much do we really know about the 8th gen chips? It *IS* possible that it's a firmware/software issue, maybe the system is overdoing it with short burst turbo voltage? Dolan, please keep on MS about this, I'm REALLY curious to see how your situation comes out. If there's anything I can do from here to help -- tests, info, w/e -- just let me know.

 

[wynand32]

Doesn't seem like the news has filtered through to here yet, forgive me if I'm missing it already being discussed (still early for me, not enough coffee).

Microsoft has already acknowledged: the SB2 power supply doesn't provide enough power to run the CPU and GPU (particularly the GPU) at 100%. It's rated at 102 watts (listed as 95 watts in the specs), and the Core i7-8650U (20 watts TDP, slightly faster than usual) and GTX 1060 (80 watts TDP) by themselves pull 100 watts. Toss in the RAM, SSD, display, and other electronics and there's just not enough power there.

So, if you slide the performance slider all the way to the right, the system runs flat out and it will discharge the battery to keep up for a certain time period. Then, it will throttle things back to keep power draw under what the power supply can provide. If you slide the performance slider to the middle or left, it will throttle everything. You'll know it's working because the fans will ramp up and down accordingly.

Microsoft could have gone with a GTX 1060 with Max Q and avoided this, but they're just essentially achieving the same thing as Max Q only not as efficiently -- they're throttling the GPU and probably achieving the same performance as if they were using Max Q out of the gate. Maybe they're not getting quite the same performance since Max Q was engineered for this.

Now, Microsoft is essentially backing off on the claims of this being a gaming system. It's not. It will do great with creative applications that use the GPU, because those tend to be intermittent. But modern games push the GPU 100% over extended periods, and the power supply just can't keep up. Maybe Microsoft knows the thermals also can't keep up, and that's why they did this. Or, the Surface Connect port can't handle more power than this. Nobody knows the specific answer. Microsoft is saying all of this is by design.

 

[Theartiszan]

The power issue is a concern, but not that big for me. When i game on this it will only be for short times anyway.
What concerns me is that the temps of the processor are getting that high. Even when only a moderate load. That wasn't anything i have seen discussed yet. I could live with it throttling only under 100% load but with loads at less than 50% that's a bit crazy here, don't you?

 

[Seneleron]

The main problem in Dolan's case is not power, it's thermals. He's hitting 100c and temp throttling, not voltage limiting to keep the battery from draining. On mine, it has maxed out at 90c, which is hot but within tJunct limits.

The other thing to remember is that MS has said it'll draw from the battery and eventually throttle with the power slider on max performance. Depending on your gaming load/duration, it may be a complete non-issue. In my case, I just wanted something with a large enough screen to play Blizzard titles [HoTS, D3, Overwatch] so as such it shouldn't have any issues. AM kind of upset that they announce this AFTER launch, as I would have thought a bit longer about the choice between this or the Blade Pro 17" 1060, but /shrug.

 

[unruledboy]

The power issue is a concern, but not that big for me. When i game on this it will only be for short times anyway.
What concerns me is that the temps of the processor are getting that high. Even when only a moderate load. That wasn't anything i have seen discussed yet. I could live with it throttling only under 100% load but with loads at less than 50% that's a bit crazy here, don't you?

I agree. and @wynand32A, I believe if it is because the many years old surface connect design, it orginally did not consider such high power/consumption. Then again, MS may renew the charger a bit, and the next gen, may redesign the surface connect

 

[wynand32]

I agree. and @wynand32A, I believe if it is because the many years old surface connect design, it orginally did not consider such high power/consumption. Then again, MS may renew the charger a bit, and the next gen, may redesign the surface connect

Regardless of the reasons, this is starting to seem like a real problem to me. The typical buyer isn't likely to consider that the machine can't run at top speed without draining the battery. That's not at all intuitive. I was prepared to go to the Microsoft Store today and drop $3000 on a system. Now, I'm reconsidering whether I can trust that it will be able to handle everything I've planned for it.

And if I were to have bought it and not be as in tune as I am with this stuff, and discovered that I couldn't use it as expected without the need to let the battery charge up again after it's been plugged in, I wouldn't be very happy. I have a feeling this is going to turn into a nightmare for Microsoft.

 

[Seneleron]

if I were to have bought it and not be as in tune as I am with this stuff, and discovered that I couldn't use it as expected without the need to let the battery charge up again after it's been plugged in

99% of people won't notice this: First because most of them will never realize there's a power slider [default set to max battery] and second because the use case has to be VERY specific in order to get it to happen [at least with the stock charger] Gaming in max performance I didn't experience ANY battery drain.

I wouldn't be very happy. I have a feeling this is going to turn into a nightmare for Microsoft

I 100% agree with this sentence regardless of my above statment.

In other news, I ran XTU with stock voltage on medium performance setting, and while temps were similar to those seen while gaming [one small peak to 90c] almost the ENTIRE TIME the processor was power throttling. 4 core speeds ranged from 2.9-3.2Ghz [totally understandable given the 4.2Ghz advertised speed is single core]. At no time did the machine THERMAL throttle. I played with a -.050 and saw no difference in performance or temps.

 

[Bill Dolan]

99% of people won't notice this: First because most of them will never realize there's a power slider [default set to max battery] and second because the use case has to be VERY specific in order to get it to happen [at least with the stock charger] Gaming in max performance I didn't experience ANY battery drain.



I 100% agree with this sentence regardless of my above statment.

In other news, I ran XTU with stock voltage on medium performance setting, and while temps were similar to those seen while gaming [one small peak to 90c] almost the ENTIRE TIME the processor was power throttling. 4 core speeds ranged from 2.9-3.2Ghz [totally understandable given the 4.2Ghz advertised speed is single core]. At no time did the machine THERMAL throttle. I played with a -.050 and saw no difference in performance or temps.

So an update for you. Spoke with Microsoft again today, and they came to the same conclusion that the CPU is just drawing too much power and there was probably a hardware issue with the unit I got. The are sending me a new unit in the mail and should be sent in the next 3 days according to them. With the holiday coming up, I suspect it probably won't be shipped till a week from now.
I attempted to under volt it a little with XTU but sadly, even the smallest undervolt was causing stability issues.
Supposedly they will be sending me a full brand new unit, even though I bought it from Best Buy and not Microsoft. If that is the case and the new one works better, that will be fine with me.

 

[wynand32]

99% of people won't notice this: First because most of them will never realize there's a power slider [default set to max battery] and second because the use case has to be VERY specific in order to get it to happen [at least with the stock charger] Gaming in max performance I didn't experience ANY battery drain.

I keep going back and forth on this myself. Contrary to my relatively harsh statement above, I think you make a valid point here. I won't say "99% of people won't notice this," probably it's a lower percentage. But it's not trivial. I'd amend my earlier harshness by saying that people who buy the SB2 for gaming will notice it. IF it doesn't affect creative apps (e.g., the Sketchup and CET apps that my wife runs, that depend on a fast GPU for decent performance), then it won't matter to the SB2's key constituency.

So, the challenge for Microsoft will be to describe this to people in a way that doesn't oversell it as a hardcore gaming system and at the same time doesn't undersell it as a powerful machine for creative types. I think they're okay relative to their MacBook Pro positioning, because even if you throttle the GTX 1060 it's still going to be faster than the AMD GPU in the Apple machine.

I'm likely going to go ahead and pick one up, particularly given the holiday return period. I'll have plenty of time to work the machine out before need to make a final decision. I'm guessing it'll be more than fine for my own needs -- I'm not much of a gamer so I won't run into that particular issue myself

 

[Seneleron]

I attempted to under volt it a little with XTU but sadly, even the smallest undervolt was causing stability issues.

That verifies my thoughts and MS' conclusions. Let us know how the new unit works... hopefully it was just a random one off.

I'd amend my earlier harshness by saying that people who buy the SB2 for gaming will notice it.

I'm not much of a gamer so I won't run into that particular issue myself

Yea, that's where I am too. It doesn't really do it with the few games I play, and apparently it'll only happen if it's set to max performance anyway, so my only real disappointment is that the surface dock can't keep it charged while gaming, which means I can't completely replace my desktop [or at least use the dock to make it easy in/out] the benefits tho. . . as good as a gaming laptop, easier to manage on the road, detachable clipboard for the plane [I travel a LOT] it's ultimately one of the best road warrior machines on the market.

--but I'm hoping at some point MS will do SOMETHING to alleviate the power draw issue. . it seems stupid to know it's a limitation of the power supply, rather than temps for once.