7760 video issue

[ccvortex]

DPM 7760, A4000 dGPU with iGPU disabled in BIOS. Was sitting reading something and blam, all video died. Forced reboot and now I have these black lines going across my screen.  Pic attached. Desktop color is black so I have a notepad window there so you can see the streaks.  Anyone see this before?

[Rinconmike]

What do you get with an external screen?  After trying that can you try turning on hybrid graphics?

 

what does it show at boot or if you go into bios?

 

 

[Aaron44126]

Looks like part of the display is working, so are those streaks fixed in position?  (They don't move around with the Notepad window as you move it, for example?)

 

Agree with @Rinconmike, checking with an external display (try duplicate/mirroring mode) or enabling integrated graphics will help determine if this is maybe an issue with the display, or with the dGPU, or something else...?

[ccvortex]

Streaks are not there on boot or in BIOS and only show up when I set the display to 120 Hz (4K display at 120 Hz). Using 60 Hz they disappear.

I have not messed with the Hybrid Graphics in BIOS because it is my understanding that you need to uninstall and then reinstall the Intel GPU drivers every time you switch that horrible feature.  Thanks all, glad to see people here are responding to posts.

 

EDIT: I have two external monitors but they are working correctly at all resolutions and refresh rates.

Streaks are fixed/do not move.

[Aaron44126]

30 minutes ago, ccvortex said:

Streaks are not there on boot or in BIOS and only show up when I set the display to 120 Hz (4K display at 120 Hz).

 

BIOS / pre-boot screens are probably running at 60 Hz.

Seems like a likely display issue to me; I'd contact Dell support and explain the "symptoms", they'll probably just want to ship out a replacement display panel.

 

I think you can get away with turning graphics switching on or off without having to mess with drivers each time now.  I recently noticed that on Precision 7X60 and 7X70, the NVIDIA GPU hardware ID does not change when you toggle this setting (contrary to prior systems), so I think the way that Windows sees the GPU devices should be "stable" between modes.

[ccvortex]

I've had issues with this laptop's video since day one - still can't use the DELL Premiere Color app without it shutting off my internal display.

[Rinconmike]

I think when I turned hybrid graphics back on, output was still on the NVidia card.  All I had to do was install NVidia driver and reinstall.  I did not have to uninstall both drivers than install intel and then install NVidia.  You may want to uninstall and reinstall NVidia anyway.

 

 

[ccvortex]

I enabled Hybrid and now the streaks show up on the boot screen et al.  They still do not appear in 60 Hz mode, so seems like enabling Hybrid switches your integrated monitor to 120 Hz? Weird.  Ran the BIOS diags and nothing found (of course).  Updated drivers; no change.

 

[Aaron44126]

2 minutes ago, ccvortex said:

I enabled Hybrid and now the streaks show up on the boot screen et al.  They still do not appear in 60 Hz mode, so seems like enabling Hybrid switches your integrated monitor to 120 Hz? Weird.  Ran the BIOS diags and nothing found (of course).  Updated drivers; no change.

 

The QR code on screen has your service tag in it, might want to block that too....

Anyway, this reinforces a bad display panel I think.

[ccvortex]

 

Bad display, I think I agree with that, appreciate the feedback.

[Rinconmike]

could it be a loose cable?  Is there a cable?

[ccvortex]

8 minutes ago, Rinconmike said:

could it be a loose cable?  Is there a cable?

This is the internal laptop display, not an external.

[Rinconmike]

1 minute ago, ccvortex said:

This is the internal laptop display, not an external.

is there a cable that connects to the internal screen? @Aaron44126 may know.

[Aaron44126]

10 minutes ago, Rinconmike said:

could it be a loose cable?  Is there a cable?

 

2 minutes ago, ccvortex said:

This is the internal laptop display, not an external.

 

There is an internal cable between the motherboard and the display.  It would be odd for it to become loose (it is secured quite tightly on both ends), but possible I guess...

[ccvortex]

32 minutes ago, Aaron44126 said:

It would be odd for it to become loose (it is secured quite tightly on both ends), but possible I guess...

 

Especially since this thing hasn't moved a millimeter in a year 😄

[sev22]

are there 7760 UHD models without discrete graphics? I found such an offer on ebay, although there is no such model on the official site ..

[SvenC]

14 minutes ago, sev22 said:

are there 7760 UHD models without discrete graphics? I found such an offer on ebay, although there is no such model on the official site ..

The Precision models typically have a "build your own" offer and the 7xxx models are pretty free about your combinations. Here in germany I can choose iGPU with a 4K display.

[Aaron44126]

48 minutes ago, sev22 said:

are there 7760 UHD models without discrete graphics?

 

Yes, you can order such a thing.  If you start with the cheapest / fully configurable model on the web site, it will let you add a UHD display without requiring that you also add a dGPU.  (For some reason, you can order 7760 + UHD + no dGPU, but if you try to order 7760 + UHD + NVIDIA T1200 — the low-end NVIDIA GPU, which should still be better than no dGPU — it will tell you that it is not a valid combination...)

[sev22]

1 hour ago, Aaron44126 said:

 

Yes, you can order such a thing.  If you start with the cheapest / fully configurable model on the web site, it will let you add a UHD display without requiring that you also add a dGPU.  (For some reason, you can order 7760 + UHD + no dGPU, but if you try to order 7760 + UHD + NVIDIA T1200 — the low-end NVIDIA GPU, which should still be better than no dGPU — it will tell you that it is not a valid combination...)

 

but the hdmi port is on the dGPU. So a laptop with iGPU only will be without Hdmi?

 

[Aaron44126]

37 minutes ago, sev22 said:

but the hdmi port is on the dGPU. So a laptop with iGPU only will be without Hdmi?

 

If you order with iGPU, there will be a spacer/passthrough card in the normal dGPU spot which allows HDMI and mDP output from the iGPU.  (I think that it uses the DGFF connector on the motherboard that you see not connected in the image above.)

 

You can swap an iGPU system to a dGPU system and vice versa by replacing the appropriate parts.  You need the DGFF card itself, plus the two DGFF data connectors, appropriate screws, and a DGFF power cable if you are installing a dGPU card in an iGPU system.

[ccvortex]

It was the display in case this happens to anyone else.