Flickering graphics caused by launcher version or integrated GPU?

Windowed mode.
1080p. Ultra Profile.

Thought so. :wink:

You probably wouldn’t see any of the flickering demonstrated above even with vsync off because Windows itself (DWM) enforces it when you’re in windowed mode. And IMO the game has always been a lot less smooth in windowed mode anyway. YMMV

I suspect this is why not everyone is seeing what I am, since I run full screen mode exclusively. And with vsync off for testing it’ll run at 150fps in 4K given the right camera view.

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After a little playing around I have identified what I believe to be the problematic file of several that change when you update the launcher beyond version 1.0.50. Updating that one file on an otherwise perfectly functioning install to the newer version (as updated by the current version of Zwiftsetup.exe) causes all the performance and graphical issues I have highlighted in this thread and the previous one. Swapping back that one file to the older version resolves it immediately. Swapping every other updated file in this manner does not have any impact, just this particular one.

Unfortunately it does not work in reverse, in that copying the old file into a new install does not resolve the issues me and others are seeing. In fact it presumably breaks some integrity check since you have to bypass the launcher altogether from that point on to get into the game.

So I believe it has to be something relating to this file and how the game and launcher interact with it. I’ve been blaming ‘the launcher’ but it’s probably to do with the files that come with the more recent installers instead.

Please let me know who I should contact directly about this, since replicating my testing requires some digging around in the Zwift system files* which probably isn’t appropriate for posting here.

*Not hacking anything here, don’t worry. :wink:


Are there other folks on this thread besides @Mike_Rowe1 who are noticing this?

I fully trust you’re seeing what you are @Dave_ZPCMR, but I’m wondering if other things specific to your setup are contributing to this issue.

Do you happen to have a second Windows machine to compare against? Completely different display, display cable and separate everything from your primary machine? For troubleshooting purposes, can you reproduce this with other variables in your graphics chain?

Yeah as noted in my previous thread where I listed some of the builds at that time, I’ve probably seen this on half a dozen different systems by now, in every combo I can realistically do. Different graphics cards (tiers, brands and models), displays and cables. Completely clean installs each time I’ve tried it (since 1.0.51), the game just performs poorly compared to what I’m used to so I roll the launcher back, which rewrites these files and we’re back to normal. Lovely and smooth motion, with no flickering at high frame rates. Done three fresh installs tonight on my main rig to test this copying and pasting strategy with the files, moving each and every one back and forth to try find what I now believe is the culprit. :rofl:


Here’s the previous thread: New launcher (1.0.51) causing stutter on Windows systems

@shooj @Dave_ZPCMR

Here is a video I just took of the sun light flickering, plus a sweet dude doing mad burnouts in the middle of the road. I have never noticed this before the recent update. I did see one other person post about the sun flickering and I think he was on Apple TV. I’m on Windows 10.

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Been on an old launcher for a while but went and updated just now to see for myself. Fanview’ed others around Watopia and in the 5 or so mins I watched others, it was evident most of the time (and would be super annoying to ride with). Win10/4k/1650super/i5-9400.

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@shooj - Same issue here immediately after taking the latest game / launcher update. Always ran on 1080p prior to this and never had this issue before, always been smooth as butter. Now affecting all my rides :frowning: :
Low resolution setting - barely usable but sun strobes badly and juddery when going round corners when there’s lots of scenery in frame.
Medium res - as above but more noticeable juddering on other riders and general scenery
High res - Unusable - juddering so bad can’t look at screen.
Windows 10 laptop / i5 / 8GB RAM / Intel HD 4000 graphics.

Anywhere I can download an earlier version of the launcher as a workaround for now?


I have a theory as to why it’s seemingly affecting people on integrated graphics too. All this may even explain why people on 10th and 11th gen iGPUs have been having crashing issues for the last few months.

Check your PMs.

I can reproduce it. Unfortunately I only have one PC but i can at least confirm it’s not the display cable. my specs are intel i5-4570, 12gb ram, nvidia gtx 1050ti, running on 1440 with display port on freesync at 75hz. there is stuttering on the newer launcher


First ride since the 23rd of March. Updated last night and rode the ToW this morning. I’ve got The Dreaded Launcher Flicker too, dammit. i7-6700k, GTX1660Ti with an LG Gaming monitor. Wasn’t doing this before I left…

How do we revert to 1.0.50 which is what I had before the forced update?

Anybody know where to find an old launcher for Mac?

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Afraid I can’t help with that one. :confused:

Mac OS user on a Mac book pro - since the update it’s been really glitchy as well; so jittery. Thought it was my internet (it wasn’t!) - I turned it down to 720 and there was no change. If anyone uses time machine you can probably go back to a time pre-update

Unfortunately I cannot confirm if performance issues people are seeing are directly related to the launcher/installer or not, especially on Mac. You need to be able to roll back the launcher to see if it’s the same problem I have (where rolling back resolves it completely). I first highlighted this in December, the only difference is that as of the latest game update, the launcher is also updated. This never used to be the case, the two were completely independent of one another. So many people will suddenly be on the newer launcher having never considered it before.

I suspect there are a couple of different things going on here, because on my laptop (integrated graphics, Basic profile) I’m seeing some daft stuff like the sun flickering. Rolling back the launcher does not help this, so I guess it must be related to the game update. We probably need to be careful not to mix up the two.

I cant take the stutter anymore so I’ve bitten the bullet and installed windows on my macbook. Dave, like with Nick, if you could send me a link to the version you’d recommend (1.0.50?) that’d be fab, thanks

I’m doubtful it’ll help to be honest. There seems to a different issue going on with integrated graphics performance. I’ll send it anyway though for you to try.

@Simon_Lockyer - With kind assistance and help from @Dave_ZPCMR I’ve found that in my case (Windows 10 laptop, integrated HD 4000 graphics):

  • With the latest game version (1.0.67624) it doesn’t make and difference which version of the launcher is used (I’ve tried 1.0.50 and the latest 1.0.52), the problem (everything juddering / sun strobing) is persistent on all resolution modes.

  • The problem only occurs when running in Full Screen mode. Switch to Windowed mode, the problem goes away on all resolutions, 1080p back to being clear and smooth as anything. Revert to Full Screen again and it’s unusable once more.

  • I’ve never seen or had this issue before the latest game update (always ran it at 1080p on Full Screen with no issue)

Any ‘fix’ that the earlier launcher versions may have been offering previous game versions seems to have been nullified by this latest game version.

@shooj Would appreciate it this can be reviewed / acknowledged as an issue?
Looks as though it’s affecting Macs and Windows from the various reports cropping up.
In my case Windows 10, integrated Intel HD 4000 graphics - Game version 1.0.67624 will not run in Full Screen mode without suffering persistent juddering / sun strobing on all resolutions. The issue is not present when reverting to Windowed mode.


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