[SOLVED] Anyone else with Displayport failure after June Windows update patches?

[yoji]

Hi all..

Per the description.. My old machine was working fine.. I started it up to do the "patch tuesday" June Patch update.. when it applied and after reboot I noticed the display did not come back.
I left it 30 mins (just to be sure it all rebooted finished restaring) but still no display
So shut it down (just a short press of on/off button) and started up again.. and nothing... no display of BIOS info or Windows.
So changed cables to HDMI and all fine.. display back and boots to windows just fine (BIOS info displays as well).
So not fully investigated.. e.g. not switched Displayport cables.. or tried different monitor... but since it was working perfectly before the patch.. and broke after.. I am inclined to think thats the issue.
I did do a clean install of display drivers (Nvidia latest 512.95 for my oldish GTX 970 card which has 1 x Displayport, 1 x HDMI and 2 x DVI outputs) but it still broken.
Rest of machine is old.. but up to date with Win 10 Pro 64 fully patched 21H2
ASUS P6T Deluxe V2 Mobo.. latest BIOS 1202.. with a slightly overclocked i7 5820k
I couldnt see any way to force/confirm the graphics card to was outputing a signal to Displayport (or any specific interface).. we just seem to have to trust it to output to all, or whatever cable connected?

Anyway - just me? or anyone else seeing this?
Or any idea how I can fix?

Thanks in advance for any advice.

 

[Fix_that_Glitch]

Did you check your monitor to make sure display port is still selected as input device? Is the refresh rate set correctly on the monitor? If those areI would recommend using ddu uninstaller to wipe all the gpu drivers clean and then reinstall them. Display Driver Uninstaller Download version 18.0.5.1 (guru3d.com) And as you mentioned using a new dp cable is worth a try

 

[yoji]

Did you check your monitor to make sure display port is still selected as input device? Is the refresh rate set correctly on the monitor? If those areI would recommend using ddu uninstaller to wipe all the gpu drivers clean and then reinstall them. Display Driver Uninstaller Download version 18.0.5.1 (guru3d.com) And as you mentioned using a new dp cable is worth a try

Hi.. thanks for your reply.
Well, I can confirm that the monitor (an HP E231) is autodetect, but set to prioritise Displayport... and can confirm then when I got no display.. I did turn off monitor.. and turn it back on (while comp was on but not showing anything).... and the monitor shows on screen it scanning all input ports (Displayport, DVI and VGA) and confirming it could find no signal on any inputs (before it decides to go back to sleep).
When I plug in HDMI (via a DVI adaptor, it is immediately detected and the screen comes to life).
Since it working fine before the reboot from the update...and did a clean install of driver (admittedly just a tick of the "do a clean install" on the Nvidia installer) we should be OK for cable and drivers.. but I will give it a go when I get back to it.
But if anyone else has input - please chip in, in the mean time
Cheers

 

[yoji]

Did you check your monitor to make sure display port is still selected as input device? Is the refresh rate set correctly on the monitor? If those areI would recommend using ddu uninstaller to wipe all the gpu drivers clean and then reinstall them. Display Driver Uninstaller Download version 18.0.5.1 (guru3d.com) And as you mentioned using a new dp cable is worth a try

OK.. got back to it..
I used the DDU to clear out the old driver..
I then reinstalled the new Nvidia drivers (516.40 released since my last attempts.. so used that)... did tick the "clean install" even though I had cleared with the DDU tool
No change.. still didnt work..
So changed cable to a known good one (from my main PC, which working fine)
No change... still didnt work..
So check monitor on my main PC... and E 231 monitor instantly worked on Displayport cable/interface on my main PC.

So think done all reasonable tests.. can only conclude that the Windows update was the trigger for the failure..
As a reminder -0 the updates installed on "Patch tuesday" that triggered the failure were:
kb5014699
KB5013887
KB890830

Any more ideas?

Cheers

 

[Fix_that_Glitch]

Give this a try, with hdmi plugged in and working, plug the display port cable in to the monitor and gpu. Go to Nvidia control panel and see if the multiple monitor settings becomes available. Check the box if it does and then try to switch over to display port for monitor.

 

[yoji]

Give this a try, with hdmi plugged in and working, plug the display port cable in to the monitor and gpu. Go to Nvidia control panel and see if the multiple monitor settings becomes available. Check the box if it does and then try to switch over to display port for monitor.

Thank you... that worked!!!
When I ticked the box to select the Displayport monitor that had just appeared... the screen went black and I thought it would fail... but after about 4 seconds it popped into life (the delay was interesting).
Once it worked.. I rebooted (with both HDMI and Displayport plugged in) and the PC behaved correctly and prioritised Displayport.. which remained working.
So shut down.. disconnected HDMI and restarted.. and again.. Displayport working fine.

SO thank you very much.. any idea what went wrong here? I am interested to try understand
Best regards

 

[Fix_that_Glitch]

Thank you... that worked!!!
When I ticked the box to select the Displayport monitor that had just appeared... the screen went black and I thought it would fail... but after about 4 seconds it popped into life (the delay was interesting).
Once it worked.. I rebooted (with both HDMI and Displayport plugged in) and the PC behaved correctly and prioritised Displayport.. which remained working.
So shut down.. disconnected HDMI and restarted.. and again.. Displayport working fine.

SO thank you very much.. any idea what went wrong here? I am interested to try understand
Best regards

It is only a theory, but what I think happens when windows updates it changes files that the gpu drivers looks for to display with. When that doesn't happen it goes to default HDMI. So when you plug both cables in at the same time it is already happy that the gpu is working with HDMI and the display port can now be turned on. So now the DisplayPort is there and you can switch over. That was my line of thinking anyway with two cables attached at the same time. Who know for certain though!? Glad you have it back.