09-06-2018 05:18 AM
Last week I got contacted by Lenovo support, and they told me the issue is solved using the most recent Firmwares, Driver and Bios. However it is not. I once again invested a couple of hours to investigate further. Thanks to mikebordon for the hint using hwinfo, makes more sense than hwmonitor. Its a little bit better than before, but for me its not solved.
I've compared a Lenovo Tab 10, a old Surface 4, a X380 Yoga i7, and a T480s i5 in Cinebench R15, 50 Loops:
I guess everybody can take out the conclusions from this graph...
This is the CPU Temperature, PL1 limit, and the Package Power of the X380 Yoga during the Cinebench loop from above:
The PL1 Power Limit slowly drops to 7W, it needs abotu 45 minutes to reach the lowest level. During this time CPU Temperature also drops, of course, under continious loat it runs at about 60-65°C. The Fan is not even running at full speed at this time. Also at the end of the test the CPU temperature drops quickly, but the PL1 limit does not get up. It needs about 30 minutes to restore to full 15W again. During the test, the CPU never goes to thermal trottle.
Compared to this, the T480s
Same test on the T480s: At the beginning the CPU hits the thermal throttle limit, then the PL1 Limit starts to drop down to 15W, while the CPU usually operates at about 75°C, with some peaks, as soon as the PL1 rises for a couple of seconds in between. After the 50 Loops, CPU temperature drops, and within 1 minute the PL1 Limit is back at the 44W like at the beginning.
I did run the same tests on a 370 Yoga (pretty much the same housing and probably the similar cooling system as the X380), and the 370 Yoga usually runs at about 10-12W under full load. Which means it performs far better than the X380, even it only has a dual core i5 CPU. I've requested a X1 Yoga from Lenovo Demopool, and I will test this, too.
I simply do not get the reason why the X380 is throttled like this.
09-06-2018 01:30 PM - last edited on 09-11-2018 04:49 AM by Andy_Lenovo
The PL1 Power Limit slowly drops to 7W, it needs abotu 45 minutes to reach the lowest level.
With the "right" load mine can drop as low as 5.5 W in a matter of minutes.
Lenovo has been pretty consistent about releasing BIOS updates once a month, so I'm hoping that we see something useful in the next few days. If not, we're giving up on the X380 Yoga.
Admin note: link removed pending review
09-21-2018 09:11 AM
Sorry for such slow progress on this, but I haven't forgotten about it. I have a trial BIOS which improves the CPU performance. I hope to be able to provide it here on the forum next week.
09-26-2018 08:37 AM - edited 09-26-2018 08:38 AM
New 1.18 BIOS released yesterday, from Sept. 20 according to the release note, with no performance fix...
UEFI: 1.18 / ECP: 1.18
- (New) Support firmware update for Infineon TPM.
One more month to wait?
09-27-2018 09:04 AM
I have a test version of BIOS version 1.18 that improves CPU performance.
To install this test version of BIOS, you can't already be on the 1.18 that was released to the website yesterday. If you are, then you have to downgrade to a previous version, first. (Note that to downgrade BIOS, you have to set the BIOS setting "secure rollback prevention" to disabled. This setting is in BIOS setup -> Security -> UEFI BIOS Update Option -> Secure RollBackPrevention. Here is previous BIOS 1.17 if you need it: https://download.lenovo.com/pccbbs/mobiles/r0suj10w.exe)
To install the test version of BIOS
1. save this file: https://1drv.ms/u/s!ApXWjQB7_a1bhftqlNVta6rm6fZAWw
2. extract/unzip the file
3. double-click on winuptp.exe and follow the on-screen instructions.
4. after the reboot, you can confirm the BIOS is installed by entering BIOS setup and looking for version "1.18_T1". The T1 is how you know that you have successfully installed the test BIOS.
09-27-2018 03:42 PM - edited 09-27-2018 04:11 PM
I have applied the test BIOS to my X380 and the results are very encouraging. PL1 Power LImits restore back to 15W once the system is no longer thermal throttled. Looks really good so far.
I've run Cinebench and UserBenchmark throughout the day and the performance scores have been very consistant.