glvn Gigabyte GA-Z97X-UD5H mobo (AHCI)
this motherboard supports enable CSM mode, but in your OLD config it was on or off ? your old SSD has been partitioned as MBR or GPT ?
I cannot say re CSM - it was never something I recall as specifically being turned on. Pretty sure the SSD was standard MBR.
Registry entries to disable dithering (only on Win 10 1903)
"DitherRegistryKey" entries? and why only on 1903 ? on 1903 this tweak works VERY unstably
Yes, I know, the reason is simply that I'm currently running 1903 for testing and the registry tweaks are the last/latest thing I've tried. I am aware how unreliable 1903 is in relation to these settings. I am of course happy to try other combinations of Win10.
The Nvidia dithering settings (I AM seeing banding in that Ubisoft image everyone refers to - but it could be the screen not dithering, and maybe my GPU still is...)
you can write a little more about this setting?
DitherRegistryKey relates to settings described here:
https://hub.displaycal.net/forums/topic/how-to-enable-dithering-on-nvidia-geforce-with-windows-os/
This is what I was referring to when I talked about screens. I have:
- Dell 2407 (my original screen - that used to work, but is now showing some vertical banding due to tired capacitors
- A second spare 2407
- Dell 2407 HC - a slightly newer version
- 2 x Dell U2410
I think on the 2407s that if I used Game mode it turns off dithering on the screen, but I'm not totally sure.
On the 2410 if you set RGB mode, it is reported that this does turn off dithering.
In applying these settings I can see banding on some images that suggests dithering is disabled. But I'm still getting eye strain - at least on the 2410 that I've been trying most recently, which is what makes me suspicious about Windows still doing bad things...
ok. you have 3 similar 970s, 2 good ones - have hunix memory, 1 bad - have samsung memory. in my opinion, a different type of memory means DIFFERENT settings in the VBIOS (not directly related to the VBIOS version number, each memory type has its own sequence version VBIOS)
Yup I have three almost identical cards as described. Agreed re VBIOS - but damned hard to actually prove.
earlier you determined that the only visual difference between good and bad 970 is the memory type (which means the initial value of the dither option is stored in the VBIOS), but I'm pretty sure that the value of this variable can be changed from the windows/NV_driver
All cards are V1.0 hardware, but with different memory (2 x Hynix == good, 1 x Samsung == bad) and apparently slightly different cooling configuration/manufacturing. This memory business is my own working theory...
previously some people have complained about a similar problem:
old motherboard + good 970 = good
new motherboard(native UEFI???) + same good 970 = bad
Ok, this I have not heard before but I'm intrigued!!
UEFI GOP it's kind of "driver/vbios" and can manage value dither option(THIS IS MY VERY BIG ASSUMPTION)
enabling CSM disables GOP, but requires MBR(and most likely reinstalling the windows - is your time 🙁 )
Hey, I'm more than happy to try this. I did a little reading and I did see descriptions of different power management functionality etc etc. There's certainly quite a bit going on behind the scenes with this stuff.
I may have to try Win 7 again, as a last gasp.
windows 7 does not officially support Z390/490 USB3 🙁
Right, I wondered about that. So much for that angle!
I've also been trying the registry tweaks, but of course that's complicated by the various Win 10 versions and Nvidia driver support.
I do not quite understand, did the "DitherRegistryKey" registry tweak help you in at least one case?
No I cannot point to the registry tweak as having "worked" - as nothing has worked. But then I've only tried turning off the dithering on 1903, and for all I know Win 10 dithering might already be off and the discomfort comes from another source.
I'll take my GPU and screen back to the original setup as well, although that screen was showing its age with vertical lines.
and now you are experiencing eyestrain with the "trusty Dell 2407", except vertical lines ?
Correct - that was my starting point ie same tired screen and GPU. New Windows install on new mobo/cpu/ram/psu.
trusty Dell 2407 and spare Dell 2407 is 100% identical ? (I understand that this is funny, but for example HP can use several OEMs for one monitor model)
I investigated this and as best I can tell they are the same. The last letter on the serial number denotes the panel manufacturer and they both read as Samsung. They are different hardware/firmware (A00 vs A04) versions which does introduce some variance, and Dell are known to slipstream different panels late in production runs without telling anyone.
One more data point - it's all comfortable using the generic display driver UNTIL I install the Nvidia driver...
AHA, Nvidia driver 🙁 !!! try 385.28+"DitherRegistryKey" (just don't ask why)
I'll definitely try that combination.
Interesting, I'd not seen that one before. I'll check that out as well.
Apologies to everyone for the massive thread hijack - I was going to start a new thread to look for ideas from folks but glvn has offered up some interesting insights. Thanks glvn!