i7-6700HQ recent power throttling

So I noticed a curious issue on my Dell XPS 15 recently (past 2 weeks or so). While gaming (and NOT on CPU benchmarks) the CPU will hugely throttle down to 0.8 GHz after about 20 minutes. I've checked thermals and while they're not great at around 80 C, that's not throttling territory either. Using Throttlestop to lower frequency and thus avoid thermal throttling still results in the 0.8 GHz throttling. I then noticed on Intel XTU that it reported 100% power throttling on the CPU.

That's what feels really strange for me, if the laptop power throttles, why do it only after 20 minutes? Also, it has never done this before the last two weeks, which is very strange. One possible issue is that since I just moved into university, by college dorm's power sockets has a power limit. Unfortunately, the 20 minutes then throttle and the fact that others seem to be fine gaming on power hungry desktops seems to point to this not being the issue. Anyone know what is causing the problem and/or what I can do to identify what's causing it?

Thanks!

 

undervolt

 

Sadly I've already undervolted by 148 mV.

 

either psu too small or the motherboard / bios has been crippled intentionally

ask for a replacement motherboard, maybe it'll fix the issue

 

If it only happens when gaming (stressing both CPU & GPU) then it's a firmware level throttle. Can you "force multiplier" with throttlestop?

As to why this never happened before, I could not say. But if you have Windows Updates running, you might have gotten a Dell update or something in them recently. It's not out of the question; I've had HP drivers show up in windows update before.

 

I've tried forcing multiplier with throttlestop and it only temporarily alleviates the throttling, but eventually it begins throttling. I might try reverting to a previous BIOS or something to see if issues are fixed.

 

Throttlestop and xtu do conflict - they are trying to write to the same registers. I would start from scratch: Uninstall xtu (it has a tendency to run in the background even when you think it is not), and delete throttlestop.ini in the throttlestop directory. Then shut down completely and restart. Then you can start Throttlestop without turning it on so you can see what is happening. Oh, and make sure there is airflow under your machine. My daughter's machine was overheating - she had set it on the couch, which very effectively blocked the intake for both cooling fans. You may also want to check your video drivers on the Nvidia site - however, I do not think that is the problem.
Keep us posted,
Joe

 

If you're overheating nothing will stop that. If your motherboard is refusing to provide power to your CPU, nothing will stop that.

Honestly? Here's what I suggest. Run XTU alone and use it in monitoring-only mode. Run a game of some kind in a window, or attach a second monitor. Turn on all the throttle warnings in XTU's information area (at the bottom; to the left is a graph and to the right are words).... current limit, power limit, heat, etc. If it has "throttle" in it, turn it on. Watch and wait until your CPU starts throttling. Whatever the throttle reason is, note it. Then, run Throttlestop while everything is still running and force multiplier. Wait until it throttles again. Note the throttle reason via XTU. I don't know how accurate the Limit Reasons is for TS8 now; I believe it had problems with Skylake in the past in terms of reporting the correct thing, however I know XTU will work for the sole purpose of reporting the throttle reason.