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I’ve been trying Windows 10 on this little laptop. Mostly the experience has been good (after removing the insane amount of bloatware). One issue that cropped up is the same annoyance that happens in Linux, PSR or Panel Self Refresh. It causes an annoying, subtle display flicker.

The problem is that in the windows default display settings there is no way to disable PSR. Lenovo does not seem to bundle the Intel HD graphics application with their driver bundle for Windows 10.

After a quick search I found this Intel KB that explains that the Intel HD graphics application has now been replaced with the “Intel Graphics Command Center”. After getting that application from the Windows Store I was able to find the setting for disabling PSR in “System > Power > Panel Self Refresh” and switch it off.

Now Windows seems to be working well on this system and I can run the Adobe apps I need for photo editing.

My recently purchased used Lenovo Thinkpad X270 seemed to run quite hot right out of the box, running the fans at full speed just copying a file across the network. Running a sensor reading program showed the cpu’s hitting 98C regularly at less than 50% load.

My first thought was to inspect the exhaust ports and heat sink to make sure they were not plugged with debris. The inside of the laptop was very clean, no visible signs of dust anywhere. So I opted to remove and replace the thermal compound from the cpu.

This fixed the issue, the laptop now idles at 30C and the highest temp I’ve recorded after a week of use is 80C. I used Arctic MX4 but I don’t think the brand matters as long as you use a quality thermal paste.

If your laptop is running hot and you feel comfortable removing the heat sink I highly recommend replacing the CPU thermal compound.

I recently purchased a used Lenovo X270 with the FHD (1920×1080) panel and intel i915 graphics. I noticed in both Windows 10 and linux that the display was flickering slightly when I moved the mouse or typed on the keyboard. Even a progress dialog box caused a slight flicker with every update. The flickering was so slight that at first I thought it was my eyes playing tricks on me but after a while it really started to annoy me.

I checked for a loose cable issue or a hardware problem with the panel and found nothing obvious. I started to think I was going to have to return the system for a refund. While copying a file I noticed that the flickering appeared to be related to screen drawing or cpu events. Even moving the bluetooth mouse would cause a slight flickering.

After some searching I discovered that the integrated i915 graphics have a feature called Panel Self Refresh or PSR. It’s

The fix was as simple as adding a kernel argument to the i915 module to disable PSR at boot time. On my Fedora 35 install this was fairly trivial using grubby:

sudo grubby –args=”i915.enable_psr=0″ –update-kernel=ALL

After a reboot the flickering problem was gone.