UHD630 - 4K screen flicker with HDMI (only during XTU stress test). No issues through usb-c. What's going on ?

[LGbr3]

Hi,

I am having many issues with my 27uk850-W monitor. I hope you can help me get some answers. 

My setup : Dell XPS 9570 / i7 (i7-8750H CPU / intel UHD 630) / 16Gig ram / 4K in built screen + LG 27UK850.

The issues : 

1. Whenever the monitor is connected by HDMI, and the laptop is under CPU load under a stress test (for example XTU), the screen starts flickering on and off. Sometimes the screen disappears completely (becomes gray or black). The extended display is still visible at this point. When the monitor is connected through USB-C, this problems does NOT occur and everything is fine (even under heavy, heavy load). I have a high-speed HDMI cable that supports 4K-5K - https://www.coolblue.nl/en/product/154321/veripart-hdmi-cable-gold-plated-1-5-meters.html.  When I connect my laptop to the TV (not 4K) then there is no problem through HDMI.

2. Sometimes, connecting through USB-C with the cable that came with the monitor works perfectly, but sometimes I get the message ' display port may be limited ' ... then for some reason it works again. This is very strange since there were no updates. That's when I switched to HDMI and found out about problem number 1.

3. I have a TB3 port on the XPS and recently bought this cable: https://www.amazon.de/CHOETECH-Zertifiziert-Thunderbolt-Kompatibel-kompatibel/dp/B074DTBN1B/ref=mp_s_a_1_3?keywords=thunderbolt+3+40gbps&qid=1568266060&s=gateway&sprefix=thunderbolt+3+40&sr=8-3  ... When I attach it to the monitor it does not work. There is no picture. Which USB-C type cable do I need ?>

By now I am getting super frustrated with the monitor. What I would actually just want is to be able to plug in an HDMI cable and have no issues under CPU load. 

Do you have any idea what the solution is to my issues? Why does the HDMI connection become unstable when the CPU comes under load? Also, why does that problem not happen when I use the USB-C cable? ALso, why does a TB3 cable not work with the monitor (is a TB3 cable not backward compatible?). 

Thanks,

Lex 

[AlHill]

What is going on is that XTU is not supported on your H processor. Only X and K processors are supported.

To stop the flicker, do not run XTU.

Also, use ONLY the graphics driver provided by your laptop manufacturer.

Doc

[LGbr3]

This is not what's going on though, because when XTU is not installed and I stress test the CPU in cinebench, or any other tool, the same thing happens. So it is absolutely not XTU related. Thanks for your answer though.

And besides that, when connecting through usb-c and testing in XTU, everything's fine.

[AlHill]

You said: "4K screen flicker with HDMI (only during XTU stress test). No issues through usb-c."

Now, for your laptop, use ONLY the drivers provided by Dell. If you still have problems, contact Dell for assistance as they are solely responsible for your support and warranty.

Doc

[LGbr3]

What is it you are getting at ? That I shouldn't be posting this here ? The 4K screen is driven by the iGPU, which is the reason I post here.

[AlHill]

Yes, you have Intel graphics. Yes, you should not be posting here. You should be using Dell support. You paid for their product and support. Make them earn it.

Look at it this way - you purchase a Ford, which has a Pioneer radio. The radio seems to have a problem. Do you go to Pioneer, or Ford for assistance? Ford provides your support and warranty.

Doc

[LGbr3]

Time to take yourself out of this discussion then. I'll decide where I post and what I do, thank you ...

[AlHill]

Have it your way. And, just as you can ask questions here, I will continue to provide answers here. You asked for support. You were told about XTU (you did not read the XTU download page), you were told about using the drivers from Dell, but choose to not listen. You choose to not use Dell support. Is there some reason you will not contact Dell for the support you paid for? You are frustrated with the LG monitor. My guess is, with your insistence on support here, that you have not contacted LG.

So, what is it you want?

Doc

[LGbr3]

You are out to have a heated discussion. That is obvious by the 'tone' you use in your posts. Besides that you are assuming that I didn't contact anyone else (Dell or LG). You should not assume things and write posts based on your wrong assumptions. That makes sense only for someone who shouldn't 'advise' others what to do.

Besides that, you assume I didn't try Dell drivers. Which is not the case either. Again, I don't appreciate being patronized, or told where to post or what to do, based on YOUR false assumptions. You don't know me (what my level of expertise is) or know what I have done before posting here.

Be nice and people will be nice to you. That's my advice to you.

[AlHill]

There is no tone to my post. Just straight answers. You did say "Only when using XTU", which is not supported on your processor. No, I do not know your level of expertise. But, I do know you did not read the XTU download page.

Ok, so let us take a step back. When I tell you Dell is responsible for support and warranty of your laptop, that is the case. If you have a driver issue, you work it out with Dell. If they determine there is a problem with the Intel driver (which they have likely modified for support of their hardware), then they will with with Intel. You also did not state if you have dual graphics. I did not look up your laptop to find out. But, if you do have dual graphics, you MUST use the Dell drivers.

There is no heated discussion here. I have given you straight answers. Your choice is to use the information, or not. As far as assumptions, did you contact Dell or not? If you did contact Dell, or use their drivers, why did you not say so? You provided a lot of other information about cables and such, but no detail on if you have worked with the integrator to resolve the problems. The fact is, again assuming you purchased the laptop new, that part of your payment is for Dell support.

Sorry if you do not understand these issues. I know you want to resolve an issue, but part of that responsibility is you working with Dell.

So, state clearly what you have and have not done, and what you want from here. Also, provide the version number of Windows 10 that you are using. If not 1903, upgrade before anymore questions.

I am going out for a while, so do not expect an immediate answer. I will be back shortly.

Doc

[LGbr3]

Your 'arguments' are 'designed' to patronize, based on assumptions 'Doc'. Let's just stop this discussion between you and I and leave it for it is.

I don't need explicitly your help.

I have my own assumption to what the issue(s) might be, but I am just asking around in order to see if someone is familiar with the problem. My choice, and not yours to make.

Besides, I highly doubt you have more expertise than myself. I may have not written a post in a way that shows any 'expertise', however you can be sure I am trained in tech. and have a pretty good insight into what issues there might be.

I don't need to 'prove' to you that I know XTU is merely a desktop program. I don't use it for undervolting or anything else because I know that it won't remember the settings on a laptop (I would use throttlestop for that - and that's not the issue either because I tested it).

I MUST NOT use Dell drivers only, because the Dell drivers are identical to the Intel drivers, just tested on Dell systems. If they don't work for my situation, I move on. And yes, I've tried versions. And no I don't have to use Dell drivers because also have a dGPU. I go straight to the source, because I've tested the Dell drivers already. For your information, it's no the dedicated gpu that pushes out the signal HDMI. Did I mention that USB-c does not give issues ? So, that rules out a CPU related issue (probably). This means it's either iGPU related, HDMI port related, or monitor related. It could also be driver related, but I've ruled that out mostly.

So, as you can notice, I am writing my question in this Intel forum as a last resort in order to hear from someone if I missed anything. There is no need for me to behave like an engineer when writing. I am not like you.

And no, it's not a NEW laptop (don't assume). And who the heck says I still have warranty on this thing ... you ? Again, don't assume.

And no, I don't want to ' take a step back '. You need to step trying to prove that you 'know' things. That might work on others, but not on me.

It's okay that you won't react immediately ... heck I don't even want your help or reaction.

If there's anyone else who has an idea about what the problem might be, I'm sure they'll react.

Ps: if I put info / link to cables I use in the post, then you can be sure I have a reason, which is: that I want to avoid anyone reacting to me that I need to use a '4K compatible HDMI cable' ... So, there you go.

[AlHill]

Have it your way...

Doc (not an intel employee or contractor)

Computers verified since 1972

[LGbr3]

Why thank you ,,,

[n_scott_pearson]

Gee, I don't want to be monkey-in-the-middle here, but I have some input - and some questions...

1. In my experience with folks describing display issues, 'flicker' is a badly overloaded term. What exactly do you mean in this case? Is the screen going blank for a second (or so) every once in a while? Is it the whole screen jittering/fluttering? Is it just the text on the screen jittering/fluttering? Is the jittering/fluttering isolated to a particular window on the screen?
2. In my experience, 90+% of all reported HDMI problems turn out to be the cable. It doesn't matter what the cable says it can do in so-called perfect situations; it is what it is doing in *this* situation. Saying 5K means nothing. Try a different high-quality cable. Do not use price as an indicator of quality; there are great cables available cheaply and there are mediocre cables available expensively. My (loose) rule: Cables that come with monitors are, more often than not, absolute crap and should be discarded. My other (loose) rule: If a monitor comes with a cable, you are probably paying a lot more for this cable than it is worth, so don't purchase this monitor with cable.
3. The output from the processor is DisplayPort 1.2 compliant. This means that, at 60Hz, it can support Standard 4K (3840x2160) with HDR or Full 4K (4096x2304) without HDR. It cannot support 5K at all.
4. I do not understand what causes the "may be limited" messages, but I suggest that, when using USB-C to HDMI, you use a dongle that is specifically designed to support Standard 4K with HDR - and which specifically *says* it supports Standard 4K with HDR. These only just recently hit the market. Here is a link to one of the three examples I found on Amazon: https://www.amazon.com/gp/product/B07N8RFW86 (I purchased this dongle and have verified that it indeed works). Also, look for dongles that say they are Thunderbolt 3 compatible.
5. Your display does not support Thunderbolt, so a Thunderbolt 3-specific cable is not going to work. I presume that, when they say it supports a USB-C input, they are saying that it supports the USB-C DisplayPort Alternate Mode. If this is the case, a good quality USB-C to USB-C cable should work.

Hope this helps,

...S

P.S. I can't close this response without pointing out a few things. Doc is absolutely correct regarding these issues:

1. You should be getting your graphics drivers from your laptop vendor. In laptops with only Intel Graphics, drivers are sometimes modified to support hardware features (Dimming controls, etc.). In laptops with hybrid graphics (i.e. those that have two active graphics solutions: Intel+NVIDIA or Intel+AMD), drivers are regularly modified to support features such as driver switching (for DRM support, etc.). Using the base driver packages from Intel or NVIDIA/AMD - which won't have these modifications - can cause these special features to stop working and/or the drivers to operate erratically. Consequently, you should not use the base driver packages unless your laptop vendor has specifically told you that you can.
2. Your primary point of support must come from your laptop vendor. If there is an issue that requires Intel's help, the laptop vendors have channels for escalating these issues within Intel. An issue escalated to Intel by a laptop vendor will have far, far higher priority than any issue arriving via Intel Customer Support. There is a *vast* difference between a laptop vendor saying that many of their customers are encountering an issue versus an issue being reported here by a single user. Bottom line, it should *NEVER*, *EVER* be considered appropriate for any laptop vendor's support personnel to refer you to Intel (to here). This is them punting on their support obligations - WHICH YOU PAID FOR! Remember that, in the case of a laptop, you do not have ANY warranty from Intel! Your warranty - for everything contained within the laptop chassis - is from your laptop vendor!

[LGbr3]

Hi Scott,

Thank you for your input. I appreciate you taking the time. Yes, I've already had discussions with Dell about this and all they ever do is ask for a service tag and go through protocol. This usually leads to more head ache than solving it myself (I speak out of experience, believe me). At the moment I am running the Dell video drivers as well as the Dell chip-set drivers. Still waiting for a response from LG. I am / was in a time rush, so couldn't sit back and wait for them, before posting here. I was hoping that I had overlooked something simple and maybe someone would tip me about it.

About your list of input points :

1. The flicker is the quickly going on and off of the external screen (the LG), while the CPU is being stressed at 100%. It happens when I use a stress test tool (XTU / Cinebench / Prime95 / etc.). So, it has nothing to do with XTU not being compatible. The problem does not occur when when the monitor is connected through usb-c. By now I am starting to think it's a faulty HDMI port on the XPS or on the LG (both HDMI's on the LG don't work, which means I lean towards the laptop). However, I'm not sure yet.
2. See above. And yes, this is a new cable, because I didn;t want to use the one that came with the monitor. And yes, it's true that 'high speed' HDMI cables are mostly non sense. I wanted to avoid someone telling me to 'use a better cable', which is why I wrote it like that in the post.
3. Yes .. I know. It should actually work without issues.
4. Actually I am connecting the usb-c cable that came with the 4K screen directly to the usb-c of the screen. No dongles. I used to get that message , but now strangely that has disappeared. It's the only way to work without the flicker problem.
5. Correct, the LG supports usb-c (connection), but not TB3. However, I had read that using a TB3 cable would work because it would 'behave' as usb-c in this case. It didn't. I had the cable for connecting a TB3 dock. I would have tested that dock if I still had it.

*** another interesting thing to mention is that : when I connect to my TV through HDMI (FHD TV, not 4K), then there is no problem whatsoever. 

EDIT

-----

With the Dell drivers, HDMI doesn't work at all. It crashes / freezes on every startup. I am officially giving op on this and will just use usb-c. It think the HDMI port on the laptop is faulty, because on both LG HDMI ports there are problems.

Thanks again,

Lex

[n_scott_pearson]

You see the screen go off (blank) and then come back approx 1 second later? If so, this is the HDMI connection being lost. The approx 1 second is the amount of time it takes for the two side to reestablish connection and monitor to get current content to display. This is the typical happening when the solution is unable to maintain the data rate necessary. I would not have thought that this would result from the processor being busy, but if it is the graphics subsystem that is being made busy, this might be a good hint to the problem that is occurring (I am thinking of other reports of this same issue occurring).

...S

[LGbr3]

It's a quick flicker that keeps on getting quicker and quicker, until the screen becomes completely gray / and sometimes white. The laptop is also 'freezing' when this starts to happen. Because on usb-c there's no problem, I thought it was not hardware related. I am not sure anymore. Maybe it's still driver related. I don't know.

Oh and I went through some step with Dell Support as well. They are lousy and behaved as expected. Just simple troubleshooting. Once they heard that the HDMI worked on a FHD TV they told me that that's where their support ends because the HDMI 'works' ... that's Dell for you.

[n_scott_pearson]

Ok, that doesn't sound like the same issue. In fact, it doesn't sound like any of the other issues I have had described. My gut reaction is it's an issue with LSPcon IC, but it makes no sense that it would occur as a result of processor being made busy.

...S

[LGbr3]

I'm actually thinking about the fact that the XPS throttles a lot. It does thermal as well as power current limit throttling. Could it be that while throttling, the data stream breaks, then when it freezes afterword, the data stream does not come back ? Since FHD is less intense on the CPU and iGPU this might not happen when connecting to a TV, however it does on a 4K monitor. Then again, why does USB-C work perfectly ?

In the end it could also just be some driver / hardware incompatibility combination. I just don't know anymore, but in my experience, the most weird problems usually have simple solutions (or not).

I might try to repaste the thing with kryonaut grizzly and put some thermal pads on the VRMs, who knows.

[n_scott_pearson]

Hhmmm, yet another case where current limiting throttling is used to cover for a cheap, inadequate cooling solution??? This does maximize profits, of course - but at the user's expense.

So, the question becomes whether throttling is somehow causing this phenomenon...

...S

[LGbr3]

Yes ... the XPS is a disaster. I bought it at a time when I didn't have another option (and I was stubborn). I think something happens when it reaches max clock speed. Some sort of freez. USB-C works though. Any idea why ?