Dell Latitude 10 ST2: Very dim screen after Windows 8.1 update & Diablo 2 gameplay

Hello community,

I just got a new Latitude 10 ST2, and I really enjoyed using it until after I updated it to Windows 8.1 and played some Diablo 2. For some reason, my brightness is now always very low, regardless of whether the adaptive brightness setting in my power plan is enabled or disabled. I can manually change the brightness, but it has very little effect. It seems the maximum brightness is really low for some reason.

I am not sure if Diablo 2 has anything to do with this problem, but I though I'd include it here since it uses very outdated graphics techniques that don't seem to be very compatible with Windows 8.1. I had to change the compatibility settings of the game executable to Windows XP Service Pack 2, force it to run with 16-bit colors and also disable desktop composition. After closing the game, some icons on the desktop still looked a bit off (they looked rather 16-bit colored and had some weird artifacts) and I had to restart the tablet to fix them. After restarting the tablet, the desktop icons were back to normal, but my brightness problem started happening.

My first attempt at fixing this problem was to format the tablet. I used my USB-stick which has the factory settings on it to format the tablet and reinstall Windows 8. The process was successful, and I had no brightness issues whatsoever. However after updating to Windows 8.1 and then restarting the tablet, my brightness problem came back.

My second attempt was to try and update my drivers. I ran the automatic updater that came with the tablet, and it updated my BIOS. Unfortunately, it did not fix the problem at all. I then took a look in the BIOS, and found the brightness thresholds under the Video section. The settings are as follows:

Brightness On Battery: 7
Brightness On AC: 15

I tried matching the battery brightness to 15, but it had no effect. The brightness problem occurs regardless of whether the tablet is connected to a power socket or not, so I was not really that surprised that it didn't work. Is a maximum brightness of 15 normal? (is it a percentage?) I don't want to change these settings without knowing exactly what they represent to avoid any damage.

My third attempt was to update the chipset drivers which includes the video driver. I installed the chipset driver, and suddenly after the screen went black a couple of times during the installation the brightness was completely restored and colors looked nice and bright again. However, when I restarted the tablet I found that the brightness problem was back. Very occasionally when I restart the tablet, the brightness is normal again, but it's super rare. A subsequent restart simply results in the brightness problem returning immediately.

A few other things to note that come with the brightness problem:
- All color gradients are not smooth. You can see the brightness differences very clearly when a picture goes from a light color to a dark color like many buttons in the Windows 8 start menu. It reminds me very much of 16-bit colors;
- Whenever I try to change the display settings in the Intel Graphics and Media Control Panel, nothing happens. It doesn't matter how much I fiddle around with the brightness, contrast or gamma, nothing changes even after applying the settings;
- The diagnostic in the BIOS said that everything is OK;
- The complete diagnosis provided by the Dell PC Diagnostics program showed that every test passed successfully.

I really hope someone can help me with this problem. The screen is so very dim, it makes the tablet quite hard to use. Thanks!

Kind regards,

StevenD91