madVR - high quality video renderer (GPU assisted)

[suanm]

Are you watching 4K movies on a display with a resolution lower than 4K?

If yes, turn off the trade quality for performance option "scale chroma separately, if it saves performance". This option will let madVR avoid scaling chroma if it doesn't have to, instead scaling luma to reach the same resolution as the chroma. Effectively this is still converting to 4:4:4, but it is probably lower quality than scaling chroma to match the luma and then downscaling in RGB.

Master,I've done the test again and again for 5 hours this morning.I get now a best way to solve the intractable problem that i expand horizontal and vertical pixels to exceed the active pixels the display allows.Chroma upscale appears now.It works perfectly.The colors of 4K videos look very great.I'm sure the conversion of 4:2:0 format to 4:4:4 format is successful.Thank you very much:thanks:

[suanm]

Have you activated supersampling? (doubling action - always supersample).

It takes a fair amount horsepower, so you might need to adjust your settings for 4k movies when it's activated.
I didn't reset what you said above about supersampling.I just did as master Asmodian mentioned in madVR specification.Nothing more was reset by me.Thank you very much.

[tingtong5]

Hi all,

I am using madvr 0.92.14 on win10 build 1703 and it stops working as soon as I want to change settings (see attachment). Any idea why this happens or how to troubleshoot it?

Thanks.

Ronald
I found out that restoring settings to default solves the crashing issue, I will have to reconfigure madvr...

[zaemon]

Custom modes used to work for me, at least with some resolution. I was mostly using 3840x2160@23. I recently changed some hardware, switched to Windows 10 and despite the fact that I have installed one of the recommended NVIDIA driver, custom mode is broken.

Do any of you has a "strategy" to try to identify what the problem might be? Despite doing a clean install of the recommended driver?

I would also be interest to have some feedback from users using custom modes at a very specific resolution, eg. 4096x2160@23. I'm a Sony projector owner and this is now my default resolution.

Thanks.

On a completely different topic, I would also suggest to clarify the scaling tabs. I feel like it could be better. Isn't possible to clearly differentiate between luma and chroma scaling? I remember one build with four options: chroma doubling and quadrupling, luma doubling and quadrupling.

Anyway, love madVR. Excellent job!

[el Filou]

As long as it runs Windows non s you're fine.The x86-to-ARM emulation is limited to 32-bit though, isn't it?
A native ARM64 binary would be faster but I don't think most developers would bother.

[FDisk80]

Custom modes used to work for me, at least with some resolution. I was mostly using 3840x2160@23. I recently changed some hardware, switched to Windows 10 and despite the fact that I have installed one of the recommended NVIDIA driver, custom mode is broken.

Do any of you has a "strategy" to try to identify what the problem might be? Despite doing a clean install of the recommended driver?

I would also be interest to have some feedback from users using custom modes at a very specific resolution, eg. 4096x2160@23. I'm a Sony projector owner and this is now my default resolution.

Thanks.

On a completely different topic, I would also suggest to clarify the scaling tabs. I feel like it could be better. Isn't possible to clearly differentiate between luma and chroma scaling? I remember one build with four options: chroma doubling and quadrupling, luma doubling and quadrupling.

Anyway, love madVR. Excellent job!

Install Geforce v390.65 driver, it's the last one that doesn't have the fubared custom resolutions.
I tried every single driver after that, they just do not work properly with custom resolutions.

[k4rma]

Hi, can someone help me? I've done a bunch of research but cant find a solution for playing a 3D MVC file.

Im running latest LAV and MadVR in MPC-HC 64bit on Win10 64bit, on a intel i5-4250u with HD 5000 graphics. Im using DX11 decoding.

I have 2D movies working fine but when i try to run a 3D MVC frame-packed file, while it displays properly on the TV, its very slow and the CPU is at 100%.

Any way to make LAV/MadVR work smoothly for these 3D movies or does my computer not have enough power?

thanks!

[huhn]

the i5-4250u that can boost quite a lot. check the temps.

you are not using d3d11 decoding is software decoded there is no support for hardware MVC in lavfilter. h264 is not a real problem for most CPU but the i5-4250u is a dual core with 1.3 ghz...

[mclingo]

Hi, can someone help me? I've done a bunch of research but cant find a solution for playing a 3D MVC file.

Im running latest LAV and MadVR in MPC-HC 64bit on Win10 64bit, on a intel i5-4250u with HD 5000 graphics. Im using DX11 decoding.

I have 2D movies working fine but when i try to run a 3D MVC frame-packed file, while it displays properly on the TV, its very slow and the CPU is at 100%.

Any way to make LAV/MadVR work smoothly for these 3D movies or does my computer not have enough power?

thanks!

i'm using an ageing i7 2700k, this uses anything from 30 - 50 % cpu on my rigg, this cpu is about 3 times faster than yours in benchmarks so its likely you are over taxing it and your setup it fine.

you're going to need to upgrade the CPU i'm afraid as I doubt MVC will every get hardware accelerated in LAV.

[Warner306]

Custom modes used to work for me, at least with some resolution. I was mostly using 3840x2160@23. I recently changed some hardware, switched to Windows 10 and despite the fact that I have installed one of the recommended NVIDIA driver, custom mode is broken.

Do any of you has a "strategy" to try to identify what the problem might be? Despite doing a clean install of the recommended driver?

I would also be interest to have some feedback from users using custom modes at a very specific resolution, eg. 4096x2160@23. I'm a Sony projector owner and this is now my default resolution.

Thanks.

On a completely different topic, I would also suggest to clarify the scaling tabs. I feel like it could be better. Isn't possible to clearly differentiate between luma and chroma scaling? I remember one build with four options: chroma doubling and quadrupling, luma doubling and quadrupling.

Anyway, love madVR. Excellent job!

If custom modes used to work for you, running DDU usually solves these issues. I know you did a fresh install of the driver, but that isn't always good enough. This has fixed issues for me with custom resolutions twice now.

I am using the latest driver with a working custom mode.

[tingtong5]

Guys, am I going crazy or is there no settings.bin file anymore? I just manually reinstalled and reconfigured Madvr 0.92.14 and now I want to backup my settings, but there does not seem to be a settings.bin file created?

Ronald

[huhn]

does madVR have the rights to write?
or with other words where is madVR installed?

[clsid]

Settings are stored in the Registry:
HKEY_CURRENT_USER\Software\madshi\madVR

You can backup/import that key with regedit.exe

[foozoor]

@madshi
You seem very quiet. :(
Can we at least know what you're working on with the math genius? ;)

[Clown shoes]

Could some of the guys having issues with custom resolutions clarify what their actual issues are?

I'm on the latest Nvidia drivers and have a custom res created in MadVR working perfectly.

I have noticed that some custom resolutions cause specific issues with my display such as green HDR but that only appears to be the closer I get to exactly 23.976.

I can get a decent custom res with everything working that only has 1 frame drop every hour or so. I can certainly live with that.

[brazen1]

I upgraded to the latest driver a few days ago. This morning I tried custom mode setup as I've succeeded doing in the past with older drivers and failed. I tried Warners guide which is slightly different than how I normally did it in the past and still failed. All is well until I get to the pop up that says to play a video for half an hour and then return to madVR and press 'optimize' again. After playing a video I select 'optimize' again and it just returns me to the define timing parameters window again as if I didn't play a video to be analyzed. No new timing modes are added. Just the few originals. Selecting 'optimize' after playing a video pops up to play a video. After 4 attempts, I gave up. Also noticed MPC players start paused and simply deleting custom timing mode stuck awaiting analyzing didn't correct. Had to reinstall driver and video starts in play mode as it should. I also noticed when using DVDFab Player (nothing to do with madVR) HDR engages but the video crawls. Reinstalling the nvidia driver cured this too. Both were fine before messing with custom mode for 2160p 23Hz. I don't doubt it works for others, I just can't get it to cooperate.

[Clown shoes]

I upgraded to the latest driver a few days ago. This morning I tried custom mode setup as I've succeeded doing in the past with older drivers and failed. I tried Warners guide which is slightly different than how I normally did it in the past and still failed. All is well until I get to the pop up that says to play a video for half an hour and then return to madVR and press 'optimize' again. After playing a video I select 'optimize' again and it just returns me to the define timing parameters window again as if I didn't play a video to be analyzed. No new timing modes are added. Just the few originals. Selecting 'optimize' after playing a video pops up to play a video. After 4 attempts, I gave up. Also noticed MPC players start paused and simply deleting custom timing mode stuck awaiting analyzing didn't correct. Had to reinstall driver and video starts in play mode as it should. I also noticed when using DVDFab Player (nothing to do with madVR) HDR engages but the video crawls. Reinstalling the nvidia driver cured this too. Both were fine before messing with custom mode for 2160p 23Hz. I don't doubt it works for others, I just can't get it to cooperate.

So after you have played at least 30 minutes worth of 23.976 material ,does the 23hz option say "custom timings, optimization data available"?
If so, when you click on this and then press Optimize again, which window are you then taken to?
You said "define timing parameters" but the two windows I have are "edit timing parameters" if I press edit and "optimize timing parameters" if I press Optimize.

[Warner306]

I upgraded to the latest driver a few days ago. This morning I tried custom mode setup as I've succeeded doing in the past with older drivers and failed. I tried Warners guide which is slightly different than how I normally did it in the past and still failed. All is well until I get to the pop up that says to play a video for half an hour and then return to madVR and press 'optimize' again. After playing a video I select 'optimize' again and it just returns me to the define timing parameters window again as if I didn't play a video to be analyzed. No new timing modes are added. Just the few originals. Selecting 'optimize' after playing a video pops up to play a video. After 4 attempts, I gave up. Also noticed MPC players start paused and simply deleting custom timing mode stuck awaiting analyzing didn't correct. Had to reinstall driver and video starts in play mode as it should. I also noticed when using DVDFab Player (nothing to do with madVR) HDR engages but the video crawls. Reinstalling the nvidia driver cured this too. Both were fine before messing with custom mode for 2160p 23Hz. I don't doubt it works for others, I just can't get it to cooperate.

Did you check to see if your custom mode was added in the Nvidia control panel? It sounds like your custom mode is being ignored and not being used/measured by madVR when playing a video with the correct refresh rate.

I ran into an issue after running DDU and installing new drivers where something seemed to be saved in the registry or madVR where custom timings were already available in the madVR custom modes menu after a fresh driver install. I went through the normal process and the custom mode was simply ignored.

I ran DDU a second time, and this time everything was set to the default in the madVR control panel under custom modes. Only then, I was able to get the custom mode to work. I don't know why it took two attempts with DDU to reset everything to its defaults.

Make sure everything is reset in madVR before attempting to create a custom mode. The custom mode panel shouldn't report any previous activity. And check to determine if any custom mode is available in the Nvidia control panel. If it's there, it is being ignored, so you can't optimize it.

[FDisk80]

Guys, am I going crazy or is there no settings.bin file anymore? I just manually reinstalled and reconfigured Madvr 0.92.14 and now I want to backup my settings, but there does not seem to be a settings.bin file created?

Ronald

Give the madVR folder Full Control permissions for Users.
"settings.bin" should appear next time you make changes.

[tingtong5]

Give the madVR folder Full Control permissions for Users.
"settings.bin" should appear next time you make changes.

Thanks! I'm gonna try that.

[tingtong5]

Settings are stored in the Registry:
HKEY_CURRENT_USER\Software\madshi\madVR

You can backup/import that key with regedit.exe
Thanks man! :-)

[Anime Viewer]

I'm encountering a problem with MPC-HC with MadVR flashing a black screen(then quickly a lighter screen that can just barely be seen) then crashing the GPU driver when entering full screen in videos. It seemed to suddenly start yesterday just before Windows notified me it had an update and wanted me to restart. I made sure my graphic drivers were up-to-date after encountering the problem, but that didn't fix it. The only way I've found to watch videos for the time being is to switch from madVR to EVR custom presenter. Obviously I'd prefer to use madVR instead.

Anyone else encounter this behavior recently? Any tips to troubleshoot or work around the issue? I've tried changing a number of settings in madVR processing, scaling, and rendering, but have yet to find any setting changes I've tried to work.

mpc-hc version 1.7.13
madVR v0.92.14
LAV 0.71.0
XySubFilter
Windows 10.0.17134 build 17134
Nvidia GeForce GTX 680M running driver version 397.64 (Nvidia Control Panel set to use this GPU)
Intel HD Graphics 4000 running driver version 10.18.10.4885

Any help or suggestions are appreciated.

[x7007]

HKEY_CURRENT_USER\Software\madshi\madVR\OpenCL\GeForce GTX 1080\x64

On this location there is DriverVersion says 385.41 , is it suppose to be newer or that's what MadVR version support ? or is it Driver detection which no working ?

[70MM]

madshi have you ever thought of creating a NLS (Non Linier Stretch) as the Lumagen can do. I have friends who buy a Lumagen just to do this one simple process, it would be great if it was a feature in madvr. https://www.youtube.com/watch?v=jwF7nYe-YzM

[nevcairiel]

You should know the answer because you asked the same question several times over the last years. I doubt his opinion has changed. Here is a quote to refresh your memory:

Do you *REALLY* want this?? I consider non-linear stretch very ugly. It looks ok as long as the camera doesn't move. But for any horizontal pans it looks totally psychadelic to my eyes, because the distortion becomes totally obvious in that situation.

I might add NLS in some far away future version, but it's very low priority because I consider NLS to be bad.

[70MM]

I dont want it for me as I use a movable Isco III lens. I have friends who would love madvr to have NLS, which is something I would never use myself, I always display all my ratios 100% true including Scope. Madvr contains a number of settings that it looks like madshi doesnt like that others asked for, which he has labeled "your the boss". However I dont use any of those settings and Im more than happy with everything from madvr for myself, my results are spectacular! My 145" scope, Isco III lens and upscaling everything to 4K I have no need for 4K BD discs, the image with 1080 upscaled through madvr to 4K is truly amazing from my JVC X9900.

[Sunset1982]

I switched my gtx1070 with my rx480 and now I am back on 1070. I now have to problems:

when I use my rx480, everytime the players osd (in this case kodi ds player) shows up, the screen goes black for 2-3 seconds (like I stitching form FSE to windowed mode) but this also happens with windowed mode... anyone knows how to get rid of it?

This annoyed me so I put my gtx1070 bak in the htpc, but now my composition rate shown in the madvr osd ist not 23,976 anymore, it is now shown as 23,980... tried different drivers, but nothing changed it back. Any idea?

[svengun]

I switched my gtx1070 with my rx480 and now I am back on 1070. I now have to problems:

when I use my rx480, everytime the players osd (in this case kodi ds player) shows up, the screen goes black for 2-3 seconds (like I stitching form FSE to windowed mode) but this also happens with windowed mode... anyone knows how to get rid of it?

This annoyed me so I put my gtx1070 bak in the htpc, but now my composition rate shown in the madvr osd ist not 23,976 anymore, it is now shown as 23,980... tried different drivers, but nothing changed it back. Any idea?

Try the CRU (Custom,e Res Utility ) app , it is free to use (google it)

PS Your signature states a GTX 1070 16GB , there are no 16GB versions... :-)

[Sunset1982]

Try the CRU (Custom,e Res Utility ) app , it is free to use (google it)

PS Your signature states a GTX 1070 16GB , there are no 16GB versions... :-)

You are right, my fault. Changed it... :D

I did a restore to the last windows restore point and now it is 23,976 again...

[joecrow]

Give the madVR folder Full Control permissions for Users.
"settings.bin" should appear next time you make changes.

Somewhat related; how can I put the settings back to default? I tried running the "Default Settings" bat with admin but no go. Did it again, Uninstalled, deleted the entire folder and re-installed in a different location/hdd but I am still stuck with my old settings.:mad:
Reluctant to mess around in the registry but how to clear settings back to default.


Win 10 x64 (1803) latest Madvr AMD RX 460 GPU.

[FDisk80]

Somewhat related; how can I put the settings back to default? I tried running the "Default Settings" bat with admin but no go. Did it again, Uninstalled, deleted the entire folder and re-installed in a different location/hdd but I am still stuck with my old settings.:mad:
Reluctant to mess around in the registry but how to clear settings back to default.


Win 10 x64 (1803) latest Madvr AMD RX 460 GPU.

Also delete this registry key:
HKEY_CURRENT_USER\Software\madshi\madVR

[mclingo]

I switched my gtx1070 with my rx480 and now I am back on 1070. I now have to problems:

when I use my rx480, everytime the players osd (in this case kodi ds player) shows up, the screen goes black for 2-3 seconds (like I stitching form FSE to windowed mode) but this also happens with windowed mode... anyone knows how to get rid of it?

This annoyed me so I put my gtx1070 bak in the htpc, but now my composition rate shown in the madvr osd ist not 23,976 anymore, it is now shown as 23,980... tried different drivers, but nothing changed it back. Any idea?

does the movie play fine after the black screen though?, if so this is perfectly normal I would say, mine takes a few seconds to switch modes and for MADVR to get started.

I've just got used to it.

[Warner306]

Any help or suggestions are appreciated.

Did you try the HD4000 to determine if it is a driver problem?

[Warner306]

I switched my gtx1070 with my rx480 and now I am back on 1070. I now have to problems:

when I use my rx480, everytime the players osd (in this case kodi ds player) shows up, the screen goes black for 2-3 seconds (like I stitching form FSE to windowed mode) but this also happens with windowed mode... anyone knows how to get rid of it?

This annoyed me so I put my gtx1070 bak in the htpc, but now my composition rate shown in the madvr osd ist not 23,976 anymore, it is now shown as 23,980... tried different drivers, but nothing changed it back. Any idea?

No one has a perfect 23.976, so this is not abnormal, but 23.980 is pretty far off. Did you run DDU before exchanging GPUs?

If so, you can create a custom resolution in madVR to improve the timing. All that is important is that you're not dropping or repeating frames with the refresh rate selected. Not that you have a perfect 23.976.

[FDisk80]

No one has a perfect 23.976

I did, it was so perfect that madVR reported no dropped frames from the beginning and to the end of the movie. Until nvidia messed up the drivers.

[huhn]

that's not his point that you can't fix it you clearly have a chance.

[valdeski]

So what is a better setting, using NGU Sharp Medium and quadruple and downscale to 1080p or NGU Sharp High double and finish with Bicubic60 AR to 1080p.
The former uses exponentially more GPU resources while not providing any improvements, I don't know maybe it's the source I am using 704x400 but doing frame comparisons it looks identical beside noise but not in a better reduced noise like the "reduce random noise" setting but in a way that it's the same amount of noise but just the location or pattern is so slightly different, if the shots weren't labeled I would totally lost track of which one corresponds to which.
On what kind of situations Quadruple is better than a higher quality first step.

[el Filou]

Have you tried NGU High double and then something like Lanczos or Jinc?

[Asmodian]

I agree, downscaling to anything over 1.5x is of dubious benefit so I would use 2x NGU high and then jinc > lanczos > cubic.

[XYZ]

Hello everybody ,
I'm trying now for a few days to set the madVR so that 1080p & 2160p movies run smoothly.
Unfortunately, I don't get it somehow (either the 4k movies are running well or the BluRays).
... seems to be a high art, to adjust the madVR well! :angry:

Does anyone of you use an NVIDIA GeForce GTX 1050 Ti graphic card with a 4k-TV, where the playback of 1080p & 2160p movies runs smoothly?
I would be very happy about his attitude to it - preferably everything with screenshots.

:thanks:

[ryrynz]

Defaults run smoothly :P reset madVR to defaults and enjoy the smoothness.
Someone needs to compile a set of profiles for various cards to avoid these same old questions.

[XYZ]

Someone needs to compile a set of profiles for various cards to avoid these same old questions.

Yes, please !

[Asmodian]

I recently got a 1050 Ti, I will attempt to make a profile tuned for it to pair with my current profiles for a 1080 Ti. :)

But it will be a few days. :(

[XYZ]

I recently got a 1050 Ti, I will attempt to make a profile tuned for it to pair with my current profiles for a 1080 Ti. :)

But it will be a few days. :(

I would be very pleased.

[nsnhd]

I recently got a 1050 Ti, I will attempt to make a profile tuned for it to pair with my current profiles for a 1080 Ti. :)

But it will be a few days. :(
Do you make a profile for 4k display ?
I'm looking for buying this card for my 1080p PJ.

[el Filou]

Do you make a profile for 4k display ?
I'm looking for buying this card for my 1080p PJ.
Here are my settings for 24/25p material for my 1050 Ti on a 1080 display:

576p: NGU Sharp, luma doubling very high, chroma very high + upscaling Jinc, downscaling Lanczos4

720p: NGU Sharp, luma doubling high, chroma high + upscaling Jinc, downscaling SSIM2D100

2160p: scale chroma separately, downscaling SSIM2D100, convert HDR using shader math complex scientific RGB clip measure each frame's peak luminance

I'm using ReconSoft for chroma upsampling on all profiles, but you should choose the one you prefer.

I'm not using any image enhancements options but you should have some GPU power left if needed.

All in all I'm very happy with the 1050 Ti on a 1080 display. Hope this helps but I'm not pretending to be a reference user. ;)

[madjock]

I have a 1050 Ti and well...

It is all very subjective for me, I think in hindsight if it was not for the HDR -> SDR Conversion to view 4K to 1080p I struggle to tell the difference, now that I have tried various concoctions and settings reading multiple guides and what people have in their settings.

I also don't understand how people can say "I do not need 4k sources on my 4k display as it makes 1080p so good!, this to me is not possible as you cannot add detail to a source, yes you may tweak an image sharpness etc, but not add anything to it as such.

I can hardly talk as I am using 4k a lot on 1080p and all the extra resources that uses including hard drive space, so what do I know.

It is also quite hard to find settings for 4K to 1080p as well, if there is that much extra detail (maybe) is there any settings that make any difference ?, how do you know what HDR tweaks to tweak if you do not have HDR on your TV.

I also find if I do not have scale chroma separately in the trade quality for performance, then I have a huge performance hit, what is the downside of this ?

I did chase the 23.976 for a while, and best thing I found was to roll back to 390.77 drivers, setup a custom res in Nvidia Control Panel, change 24 in refresh rate, then select Timing, select GTF to get those settings, then select Manual so you can edit them, and change the lower setting of 24 to 23.976. It is as near as dammit and floats between 23.9759 to 23.9762 or something, think I had it even closer at one point, but using Insider builds with Win 10 things change all the time as you can imagine.

I gave the MadVR custom settings a shot but found either they would not take, gave me a fuzzy picture or generally was a waste of time messing about with, but ultimately I started thinking Ive managed for years without worrying about 23.976 dead with Kodi using the standard Video player and never noticed any issues, so step away from the fixation I said and watch some films. :D

I started using the test MadVR that was going about, and then .14 when I found out there had been two updates inbetween, but I could be wrong but I have never seen any info on what to chose with all the new HDR to SDR settings and what they do ?. It is also hard to find what people use fro NIT settings as well.

Also how the heck do you stop MadVR settings from being on the top of everything all the time ? or am I thick ?. :D

[Anime Viewer]

Did you try the HD4000 to determine if it is a driver problem?

I forced it to use the Intel HD 4000 GPU instead of the Nvidia 680M, and playback appears to function at full screen (granted settings need to be reduced to minimums to not have drastically high amounts of glitches and render times).

I've also found that while the screen / mouse cursor is flashing right before driver crash if I : 1) drag the mouse to the bottom of the screen (bringing up the seek bar),2) press the Windows key, 3) have an on screen settings popup box (like madVR settings) forcing d3d9 windowed mode video appears and plays, and the GPU doesn't crash while any of those things are active on screen.

In summary (after the Windows update auto applied 5/13/18):
MPC-HC + madVR + LAV + XySubfilter using Nvidia 680M= fails to play full screen
MPC-HC + madVR + LAV + XySubfilter using Intel HD 4000 = plays in fullscreen successfully
MPC-HC + EVR Custom+ LAV + XySubfilter using Nvidia 680M = plays in fullscreen successfully

Edit:
by going into madVR settings -> rendering -> windowed mode and unchecking "present several frames in advance" making the videos run in D3D9 windowed (old path) I am able to play the videos at full screen.

[Warner306]

I have a 1050 Ti and well...

If you're watching mostly 1080p at 1080p, then this is basically passthrough. If comparing to Kodi VideoPlayer, it simply renders pixels less faithfully. If you switch back and forth long enough, you will notice very small differences in color and occasional noise in VideoPlayer, but it is not a major change. madVR should also be slightly sharper, but this can be difficult to detect. But that's how the content was mastered. If you want it to be sharper, sharpen the image. If you want less noise, use artifact removal. But, mostly, the pixels are being rendered faithfully without adding any artificial detail.

If upscaling 1080p to 4K, you can indeed add detail to the image. Image upscaling will approximate what a low resolution image would look like if it was a high resolution image. There are four times as many pixels in a 1080p source upscaled to 4K. Unless you use Nearest Neighbor for upscaling, those new pixels will add detail to the image that was not there previously.

If you scale chroma separately, the chroma layer will be slightly lower quality. This is not overly important when doing a large downscale, so you can check this if you need to save resources. The only thing important is the quality of image downscaling. I would recommend using SSIM 1D 100%. If you select this, you may be able to uncheck the chroma quality checkbox with your graphics card.

As for HDR -> SDR conversion, it is completely up to experimentation. There are many settings because it is a work-in-progress. The setting "dumb - convert gamut late" is popular, while there doesn't seem to be consensus on the best scientific method. The target nits is like a brightness adjustment, and you can use any value you want, as long as the image looks good to your eyes. There is no scientifically accurate value. Higher target nits will crush the low end in attempt to increase the detail of the specular highlights at the top end, but this can lead to black crush at high enough values.

I don't know what you mean by having madVR settings on top of everything all of the time. Just close it if it is stealing focus from other windows.

[jkauff]

Also how the heck do you stop MadVR settings from being on the top of everything all the time ? or am I thick ?. :D
I have no way of evaluating your thickness, but Ctrl-J toggles the on-screen display. :)