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Surface Pro 4 i7-6650U power throttling issue?

Mike007

Member
Anyone try turning hyperthreading off, and downclocking the CPU to like 1.7GHz or 1.5GHz to give the GPU more power room to breathe?

I have tested mine and downclocked my i7 CPU to 1.8ghz using windows power options and ran heaven bench whilst XTU is open. It starts off at 25w TDP as normal but eventually, it will drop back to 15w without a fan. (takes a little longer)

Something else I have found out recently, If you use a fan to keep the TDP at 25w then the battery will drain because the adapter doesn't give out enough power. On mine it drains at about 20% per hour whilst plugged in and gaming.

If you let the TDP drop to 15w then the battery wont drain.
 

jason10mm

New Member
Something else I have found out recently, If you use a fan to keep the TDP at 25w then the battery will drain because the adapter doesn't give out enough power. On mine it drains at about 20% per hour whilst plugged in and gaming.

You know, I see this on my SP1 when gaming (I also use a power cover). The device is hot and I lose battery despite being plugged in. I figured the heat kept the battery from charging or there was a software issue with charging + heavy use. Could be what you describe as well. The drain is not as fast as NOT being plugged in, but it is there. This is acceptable but sub-optimal) on a device like this, but I'd like it if they could supercharge the device when plugged in.
 

jbowden

Member
i have i7 16gb 256gb SP4 and the fan only comes on during heavy loads while watching videos. it rarely comes on...almost never.
 

PumpkinPie

New Member
I have tested mine and downclocked my i7 CPU to 1.8ghz using windows power options and ran heaven bench whilst XTU is open. It starts off at 25w TDP as normal but eventually, it will drop back to 15w without a fan. (takes a little longer)

Something else I have found out recently, If you use a fan to keep the TDP at 25w then the battery will drain because the adapter doesn't give out enough power. On mine it drains at about 20% per hour whilst plugged in and gaming.

If you let the TDP drop to 15w then the battery wont drain.

Interesting, so it seems the adapter might actually the problem, it's just not giving enough juice. I think with a 45w/50w adapter maybe this problem could be solved.
 
I bet if you browse the internet, in a few minutes, the back will get a bit warm. And you can hear the fan come on in a quiet room. Mind you I live in Hawaii and right now, average indoor temp is about 76-78deg. I have the same unit as you.


i have i7 16gb 256gb SP4 and the fan only comes on during heavy loads while watching videos. it rarely comes on...almost never.
 
Interesting, so it seems the adapter might actually the problem, it's just not giving enough juice. I think with a 45w/50w adapter maybe this problem could be solved.

Yes, just browsing the web (edge is a resource hog) but checking task manger CPU is just at 20% and the fan is on. My Surface Pro 2 i5 doesn't even do that
 

Mike007

Member
The new surface dock has a 90w charger with it. I wonder if this would alleviate the battery drain on a fully loaded 25w i7 when plugged in.

Does anybody with an i7 have the new dock and is willing to do a few tests?
 

PumpkinPie

New Member
But does it actually charge the SP4 faster?

It doesn't need to, it just needs to supply the SP4 with enough juice to (hopfully) alleviate power throttle, if it is in fact what the problem is. At 65w, that should be more than enough to adequately satiate the i7 SP4's power hunger, which would in turn, prevent the battery from draining while plugged in and doing heavy tasks like gaming.
 
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