In my MSI GS66 thermal testing video I mentionedundervolting was locked, however I’ve found out how to unlock it, so let’s take a lookat how to do this and see what sort of a performance improvement we can expect from undervoltingthe GS66.
So far all 10th gen Intel laptops I’ve testedcan’t be undervolted with Intel XTU or Throttlestop, presumably due to the Plundervolt vulnerability.
I’m not certain, but think that undervoltingin BIOS should still be possible, as long as the BIOS supports it.
After skimming the Plundervolt whitepaperit sounds like the bug is exploited through the software’s ability to apply undervolting.
With the Gigabyte laptops I tested I didn’tsee a way of doing that in the BIOS, and by default the GS66 doesn’t offer this either, that is until you enter the advanced mode, which is as easy as pressing right shift, right control, left alt, and F2, obviously.
Once in this mode, go into the advanced settings, scroll down to the overclocking performance menu, enable the overclocking feature, thenfrom here you can change XTU interface from the default of disabled to enabled.
Interestingly there are no warnings aboutsecurity issues or anything when changing it, it just lets you enable it.
We’ve also got the option of undervoltingthe CPU through the BIOS itself, so this can be done even without using software like XTUor Throttlestop if you prefer.
Personally I prefer software, so have enabledXTU Interface, it’s easier to recover from when things aren’t stable.
It makes perfect sense that we get the optionto change these things in the BIOS, it’s an unlocked K processor, so I’d be disappointedif that wasn’t the case.
That said, fortunately this feature isn’tlimited to the GS66 laptops with K CPUs, Tim from Hardware Unboxed confirmed that the i7-10750Hmodel of GS66 also allows you to enable undervolting and undervolt through the BIOS in the samemanner.
After saving the settings and booting intoWindows, I confirmed that undervolting was now unlocked in XTU and worked as expected, so let’s check out some revised thermal testing and see how this helps.
All testing was done with an ambient roomtemperature of 21 degrees Celsius.
The stress tests were done by running Aida64with only stress CPU checked and Heaven benchmark at the same time, while the gaming resultswere done playing Watch Dogs 2.
I’ve highlighted the new undervolted datahere, I didn’t try to tune the undervolt and just selected -0.
1v, a value I’d expectmost to hit no problem.
We can see that temperatures haven’t reallychanged on the CPU when under stress test, but the GPU gets a bit cooler, presumablydue to the shared heatpipes, changes to the CPU do affect it.
In the games we were just seeing slight 1degree improvements on the CPU, though more of a change to the GPU temps.
I’ll also note that although the thermalthrottle limit is set to 95 degrees celsius, I did see the option to boost this in theBIOS.
While I could have done this to squeeze outsome extra performance, I probably wouldn’t recommend it just for longevity, 95 is alreadya fairly high limit in my opinion, if it were my machine I might be more inclined to capit to 90 instead.
Regardless, it’s cool that the option isavailable in the advanced BIOS.
These are the clock speeds for the same testsjust shown.
We’re seeing a nice boost to the CPU performance, especially in the stress tests, around a 300MHz boost over all 8 cores for such a simple changeisn’t bad at all.
The games also saw a similar fair improvement, I think with all improvements in place the 4.
4GHz all core turbo boost speed was beinghit.
It was interesting that it didn’t go higher, because XTU reports the all core CPU boost speed as 5.
3GHz, so there may be some settingin the advanced BIOS that needs to be adjusted to affect that.
Either way, I can’t complain about thisperformance especially when you remember the CPU was at 83 degrees here.
When looking at the TDP reported by hardwareinfo we’re not seeing too much change here, and this is because the power limit was stillbeing hit, but the undervolt allows us to get more done within the power limit available.
Boosting the power limit in XTU didn’t doanything to help, even though PL1 is set to 65 watts, so I might need to get into theBIOS to boost it up further.
The power limit dynamically boosts up as thermalsimprove, which probably explains why the power limit boosted in the stress test with theundervolt applied, it was running cooler.
Here’s how Cinebench performance improveswith the same undervolt in place.
It was possible to boost the multicore scoreby 11% with this honestly pretty average undervolt, you could definitely push it harder.
CPU only clock speeds improve a similar amountwith the undervolt in the Aida64 stress test.
We’re still power limit throttling, howeverthe undervolt allows us to get more work done within the power limit.
The undervolt also drops the temperature justa little extra despite also offering better performance, so you could definitely takeadvantage of this and mod the GS66 further with the billion options in the BIOS if youknow what you’re doing.
There are plenty of settings in there so youcan tune until your heart's content, but as bob of all trades mentioned on twitter, ifyou don’t know what you’re doing you could do some damage.
Let me know what you thought of the improvementsby undervolting down in the comments, I’m just glad that it’s still possible withthe GS66 even if it is a little out of the way and slightly hidden unless you know thecrazy shortcut for advanced BIOS, and if you’re new to the channel then get subscribed forfuture laptop and tech videos like this one.
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