Hello Kalwi, thanks for joining the Graphics community.
I was able to make a test using a Dell ultra book and a DZ87KLT Intel Motherboard. Both devices use HD4600 and the latest Graphics drivers available.
I changed the resolution to 1024x768 and after a system restart, both systems maintained the resolution previously selected.
I would suggest you to test another monitor on this computer. You may also want to try a different cable and also check if there is a new BIOS version that you can try to install.
Wow - having the same issue
OS : Windows 8.1
Hardware : HP EliteDesk 800 Mini
Display: Dual HP displays connected via DisplayPort
Driver version 10.18.10.3960
When PC comes out of sleep the secondary (Not primary) screen comes back on at very low resolution of 640x480
Disconnect Displayport cable and re-connect which is not acceptable
Query - At power on no issues??
I have the same issue on a brand new Dell M3800. I downloaded the Windows 7 driver for the HD 4600 Graphics driver. After installation it gave me a resolution of 3840x2160. After setting the resolution to 1920x1080 I rebooted and it reset back to the higher resolution. I ended up removing the driver altogether until I can find a fix.
Barttrek, could you please try this procedure,
If you do want to overwrite the drivers with the Generic Intel drivers, follow these steps exactly. Note, you will lose any customization made in the drivers specifically for your system and the system may not function as expected.
Download the zip version of the generic Intel HD Graphics driver here: https://downloadcenter.intel.com/download/24785/Intel-Iris-and-HD-Graphics-Driver-for-Windows-7-8-8-1-64-bit
Extract it to a folder on your desktop.
1. Login with administrator privileges
2. Open Control Panel
3. Open Device Manager
4. Click on "Display adapters"
5. Double click "Intel HD Graphics"
6. Click on the "Driver" tab
7. Click on "Update Driver" button
8. Click on "Browse my computer for driver software"
9. Click on "Let me pick from a list of device drivers on my computer"
10. Click on "Have Disk" button
11. Click "Browse"
12. Navigate to the folder that you unzipped the Intel HD Graphics driver to
13. Navigate to the Graphics sub-folder
14. Double click the igdlh64.inf or igdlh.inf file <-- depends on if you have 32 or 64 bit OS
15. Click "OK"
16. Click "Next", Driver should now be installing.
17. If successful, click "Close", Reboot.
Please let me know the results,