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07-14-2020

IL

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connecting laptop to external monitor slows the laptop.

2020-07-14, 12:04 PM

P1 gen2, when connected to external monitor, becomes unworkable. even the mouse drags slowly.

 

any clue why is that? known issue?

 

thanks


E

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548 Posts

10-03-2011

CA

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Re:connecting laptop to external monitor slows the laptop.

2020-07-14, 18:50 PM

More likely than not - nVidia Optimus issues. 

 

Restart GPU driver (Win+Ctrl+Shift+B). Upgrading BIOS and the GPU driver to the latest might help.

 

If this doesn't help, the nuclear option is to set GPU to "Discrete Only" in BIOS, and turn on Optimus only when you're away from the monitor and need that battery life.

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06-13-2013

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Re:connecting laptop to external monitor slows the laptop.

2020-07-14, 23:37 PM

@ MENDEL111 wrote:
 

 

P1 gen2, when connected to external monitor, becomes unworkable. even the mouse drags slowly.

 

any clue why is that? known issue?

 

 

Are you running "hybrid" or "discrete"?

 

Do you display on both laptop screen and external monitor, either (a) "clone mode" 1|2 displaying same on both displays, or (b) "extended desktop" mode with displays #1 and #2 having independent resolution and scaling? Strange issues across re-boots if "extended desktop" mode is in effect and the external monitor is present and connected, at least on my P73 and P70.

 

Or is the laptop screen set to "dark" when you have the external monitor connected, i.e. either (a) "display on #1 only" or "display on #2 only"?  No matter which setting is in effect the laptop screen will always be activated and receive output if there is no external monitor connected. And also no matter which setting is in effect the external monitor will be activated and receive output if it is connected and the laptop screen will be set dark.

 

I recently got a P73, run in "discrete graphics" mode (as I also run my P70), and had connected an external monitor. I don't really need to have the laptop screen in use when I'm in my office and using a large external monitor right in front of me. But because this was the first laptop I've gotten with a 4K screen I decided to leave it on, in "extend these displays" mode.  I arranged the monitor icons properly in Desktop Properties, set the unique resolution and scaling for each display #1 and #2, made the external monitor (#2) my "primary", and everything was running fine... for days, actually, until I had to re-boot.

 

And the re-boot didn't come up properly. Instead "primary" external monitor (#2) remained black.  And on the secondary laptop screen (#1) the screen was also dark but the taskbar was only very skeletal, having a gray color and a Windows start button on the left. Nothing else on the taskbar appearing on the laptop screen, no taskbar of any kind nor anything else on the external monitor. Also the system was totally unresponsive to mouse or keyboard.  But strangely, Windows itself was actually running... but "in the dark"!  I could do CTRL+ALT+DEL and the task manager interrupt screen appeared (on the primary external monitor screen as it should).  I could remotely connect to the P73 using Team Viewer Client and RealVNC Client on another machine, and both Team Viewer and RealVNC host software on the P73 would respond. It was just that the desktop had not been completely painted on both monitors.

 

In desperation, I held the POWER button down for 10 seconds, to manually cause the P73 to shut down (actually, the running Windows "in the dark" actually did truly shut down gracefully).  And then I pushed the POWER button again to re-boot.  And now, this second time re-booting, like magic everything came up normally with output going to both primary #1 external monitor as well as to secondary #2 laptop screen.

 

And this pattern persists. Every other re-boot "fails" (i.e. has the "dark Windows" system with partial taskbar on secondary screen), and then press POWER for 10 seconds to manually force Windows shut down and then re-boot for a second time and everything now "works" perfectly.

 

Astonished, I tried the same thing on my P70. And the identical failure occurs. Perhaps this is something new born from Win10 1909 (or some other version), or something in the current BIOS for P70 and P73 when using "discrete graphics", or maybe some interaction between nVidia driver and "discrete graphics". The problem doesn't occur if you have "display on #1 only" or "display on #2 only".  Doesn't occur if you have "duplicate these displays".  Only occurs if you have "extend these displays", perhaps also when there are different resolutions for the two screens as I do.

 

Anyway, I tell this story by way of "warning" regarding something relatively recent that is now occurring when (a) you run in "discrete graphics" mode, although to be honest I didn't test in "hybrid graphics" mode since that's just not the way I operate, and (b) you use both external monitor and laptop screen. If you are perfectly satisfied only using the external monitor when present, or the laptop screen if the external monitor is not present, then just set Desktop Properties to "display on #2 only" and all will be well.  You won't see the "dark Windows" symptom.

 

I don't know if any of this is relevant to your P1 issue, but I wanted to get my recent P70/P73 experience out there when an external monitor is used. And it doesn't matter whether the external monitor is connected via DP or HDMI, using the HDMI port or miniDP or USB-c Thunderbolt3 port on the laptop.  The issue seems to be port-independent, but tied to "discrete graphics" and "extended desktop mode".

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07-14-2020

IL

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Re:connecting laptop to external monitor slows the laptop.

2020-07-16, 11:26 AM

I will check your suggestions and report back. maybe it was the cable I used to connect the external monitor. Perhaps I used the USB C to conncet to the screen. 

I'll finish some tasks at work and try to make time for some testing.

 

Thanks a lot for the help and elaborate answers.

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