so it took me couple days to troubleshoot screen flickering issue on this laptop. After going through all driver related updates, and trying out drivers directly from Intel and Nvidia, and using DDU to uninstall any previous drivers, it turns out to be a BIOS related issue. This took one flicker when I was looking over the BIOS menus to figure out it is not software related.
Under the "Video" tab in BIOS there are 3 options:
- Enable Switchable Graphics - this one enables the integrated GPU, i.e. the Iris Pro P580 in my case. Otherwise the system sees only the discrete one, i.e. the NVidia M2200. Enabled in my case.
- Enable Dock Display Port Through Integrated - this one enables docking station DVI#1 or DP#1 interface to run external display over the integrated GPU when switchable graphics is enabled. I don't have DP on my docking station though. Enabled in my case.
- Discrete Graphics Controller Direct Output Mode - this one enables external monitors to be run over the discrete GPU only. Disabled in my case.
I've got a docking station with two DVI outputs that are connected to two Dell U2412M monitors, and what I see with the latest BIOS (1.15.x) is this:
(3 min video, copy and paste in browser address bar if it doesn't show as a link)
If I don't have the external monitors, the laptop screen would flicker similarly. So I had to flash the BIOS a total of nine times to get to a BIOS version that doesn't have this screen flickering issue. History of this as follows:
1.7.1 - shipped with the laptop, which is manufactured in March 2018. Updated to:
1.15.1 - the current version as of today, screen flickering noticed but could not be directly linked to the BIOS update due to windows 10 also updated to the last 1903 version, and display drivers updates followed as well;
1.14.1 - screen flickering issue. Had to update twice to this version as the first time Windows 10 automatically updated back to 1.15.1 after computer restart due to the Device Manager "System Firmware 1.15.1". Duhh I've updated that driver as well when I did the 1.15.1 BIOS update so now had to disable this in Device Manager so that windows doesn't update automatically back to it. Otherwise it should show as "System Firmware 1.0.0".
Note when downgrading BIOS, the Intel Management Engine (VPro) will not downgrade from later version, so every time I downgraded bios it failed with "ME Firmware EndUpdate Failed Error: 0x00002236". No worries, other things update just fine, but this particular one stayed as version 18.104.22.16890 through all BIOS downgrades.
1.13.0 - screen flickering issue, though not so frequent but still existent;
1.12.2 - screen flickering issue;
1.11.1 - screen flickering issue;
1.10.2 - screen flickering issue;
1.9.1 - working fine without screen flickering issue !!!
Please see what was changed between update 1.9.1 and update 1.10.2 that caused this screen flickering problem that carries all the way to the current last BIOS 1.15.1 for laptops that have the Intel Xeon 1545M v5 processors. I'm certain that this relates to the higher level integrated GPU (Iris Pro P580), so likely laptops with Xeon 1575M v5 could also have the same issue.
I've got screenshots of all BIOS downgrades, I can post in case there is an interest for these.
On the bright side, I've got another Precision 7520 at work that has Xeon 1505M v6 with P630 integrated GPU that works just fine over the 1.13.0 BIOS that I believe came with the laptop. I haven't updated that one with the newest BIOS yet.
Can I expect a fix for this in the next BIOS release, after I pointed where to look for the problem? Asking as there's no reply to this post yet. Nonetheless this is top of the line model that came with premium price tag.
The problem started with BIOS 1.10.2 update, and what was changed was this:
- Fixed incorrect Windows operating system logon message.
- Fixed system password not prompted when booting the system with NVMe SSD.
- Fixed Legacy PXE boot issue that affected the Dell USB-C Mobile Adapter - DA300.
- Fixed Blue Screen of Death (BSOD) error code 0xA5 in Windows 7 32 bits.
- Fixed serial port device on legacy dock is not functional.
- Supported selectable MAC Address Pass-Through feature in BIOS Setup.
- Enhanced SMM Security Mitigation feature.
- Updated Enhanced Pre-Boot System Assessment (ePSA) firmware.
- Updated Realtek USB LAN firmware.