Quote from: Dave S on July 24, 2018, 00:24:48
Just don't update the BIOS or you'll need a new laptop. Happened to my 9550.

Can you provide some more information about this? Which steps caused problems for you? Did you undervolt your CPU first and then update BIOS?

Thanks!
Philip

Hello to everybody, I'm new member and I'm trying to undervolt my Dell XPS 9570 i7 8750h, 32 GB RAM using Throttlestop.
Even though I read a lot of tutorials about it, I still have some doubts.
I started to do tests from - 50mV with TS Bench built in, the machine didn't crash but i was able to get 0 errors at 1024M and 12 threads only around an undervolt of -113.3 mV for core and cache... if I try to undervolt less, i start to get a lot of errors and around -140 mV I get tons of errors despite no BSODs with Prime95 (for 12 hours) or Aida64.
After asking for some help, I discovered the great Linpack Xtreme to test the stability, but I'm not sure how to set it up...
I tried to set it using 30 GB of Ram (experimental) (problem size: 62897), with the maximum of trials (also if i could set something like 3) and all of cores.
Unfortunaly, most of times, my system gets freezes or Bsods before to finish the first trial, also with a voltage offset of -113mV or -105mV...
It seems i can't undervolt anything.
This looks like very strange... because with other stress test software like Prime95, I can continue the test also for 12 hours (I tried with -140mV) without any errors or Bsods.
I read that all the people who have this machine (with i7 8750h) are able to undervolt it also with -140mV ore more... at least with -120mV.
Is there anything I do wrong? How should I set Linpack Extreme for my machine to be sure it is stable?
Or maybe isn't my laptop so lucky or has any issues? I don't know if an undervolt which is around -70 or - 80 mV still makes sense for this pc/cpu model.
I'm quite disappointed.
Thank you for your help.

FYI:  I found that the Intel XTU program tended to lose its voltage offset after waking up from sleep (on a Dell XPS 15 9570). 

Opening XTU suggested that the offset was still in place, but in reality, benchmark scores clearly showed that I was back at stock voltage.  Pressing "enable" again brought the expect performance.  It seems that XTU is not 100% reliable with this regard.

Some folks have suggested that Thottlestop might do a better job of maintaining persistent voltage offsets after reboot.  That's what I plan to try next.  But I'd be curious to see if others are experiencing similarly flaky behavior with Intel XTU across sleep/wake sessions.

It'd be nice if you could tell us how other cpu's (such i5 8300h and a tdp unlocked i7 8550u or i7 8650u) compare aswell.

What is the default vs undervolt clocks, temps and power consumption for them? are they any more or less efficient?

I'd expect them to run at 3.9 ghz at lower temps and less power consumption due to having less cores / threads. But I wonder how much the difference it really is and at different clocks speeds aswell (3.2 ghz, 3.6 ghz, 3.7 ghz )

It's not so bad. But scores over 1200 which occur in "rankings" are only in the first loop. after that, it stabilizes at 1170, still ok, but it's a score which I get with razer 15 easily at 80C. Again, The problem is that it could be undervolted very slightly.  :-\

Why don't you undervolt even further?
It has been widely reported that you can easily undervolt core with at least -135 mV and Intel GPU with -50 mV. Stable under ANY stress.
But many people can do even lower than that, I guess depends on an individual machine.
Please try at least -135 mV and redo the tests!

Just don't update the BIOS or you'll need a new laptop. Happened to my 9550.

I have just done the same testing on mine with 8750h 175mv undervolt and got very similar results.

Brilliant that you added this extremely useful information.

I would be thrilled to see the other big laptops with i7 and i9 CPUs to have a small section where you do the same benchmark test with maximum possible stable undervolting values.

The Alienware 15 R4, Lenovo ThinkPad E480, T480 would also benefit from it. Many people are comparing the XPS 9570 with the above Alienware, so a side by side undervolting result value would be wonderful.