C Sync working for 16.2.1 but not in 18.5.1 - R9 380

[mrchrister]

Hey guys, just upgraded my 7750 to a R9 380 for Wii and Naomi gaming.

I have a weird issue. Everything works perfect with 16.2.1 but I cant get C Sync working with 18.5.1 in 640x480.

Tried all sorts of reinstalls over the last 3 hours, also changed polarity in my Generic_15 preset but that made no difference. 18.5.1 works if I switch to any other resolution than 640x480. 2560x240 works with no issues, so does 320x240, but 640x480 is just a garbled mess. No problems with 640x480 resolution in 16.2.1
Looked through the forum but it doesnt seem to be a common issue... I'm on Win7 64bit. Does anyone have an idea why this isnt working for me?

I would love to take advantage of new Vulkan Drivers for some of the Retroarch cores and as I understand it, its better to use 18.5.1

[Calamity]

Hi mrchrister,

It sounds like 640x480 is the mode that was enabled by EDID emulation, and for some reason it doesn't get overridden by the c-sync redefinition of its modeline that's applied by VMMaker when installing modes.

Can you check if you have 2 instances of 640x480 in Arcade OSD? Like @30i and @60i.

[mrchrister]

Thanks for you feedback, @Calamity !
I do have a 30i and 60i setting in ArcadeOSD in 16.2.1 and 18.5.1

[Calamity]

Then you probably need to choose the other 640x480 instance.

[mrchrister]

Tried both and both display the same issue.

I'm not sure it is a csync issue TBH. I noticed with composite sync off and adjusting vertical sync on the PVM I can see that 640x480 works correctly. When Csync is enabled it gives a diagonal distorted picture as if it is out of sync somehow.

Any idea why the two driver versions behave differently here?

[kill_one]

I have the same card and I have a similar problem but with the 16.2.1 crimson drivers in Windows 7 x64, with the 640x480 resolution it often gives me black screen it does when I mainly launch Type x or Teknoparrot games and often stays like that when I go back to the desktop , to restore it I have to change it by hand, put another resolution and then again choose 640x480 ... when the screen is black via vnc the game shows up so I think the game wants to start with 640x480p and not 480i and having the jammasd card I get the black screen when the resolution goes out of sync, if I go to the settings of the windows card I give 30hertz interlaced or 60hertz, 60hertz interlaced not c0p while in arcade os both 604x480 30i and 640x480 60i are listed, also after a while in interlaced resolutions the screen starts to wobble exaggeratedly to the point of hurting your eyes by turning the monitor off and on again after a few minutes you can see it correctly again.

[mrchrister]

I will clean all and drivers with ddu and try from scratch. I also have a win 10 install I could use for testing. Will report back

[psakhis]

I think it's a "register problem" on windows; some emulators or programs use 640x480 30khz by default, skipping 15khz mode.

See post http://forum.arcadecontrols.com/index.php/topic,163106.0.html

I resolved this issue in my cab but i don't know how..i was playing around ChangeDisplaySettingsA and EnumDisplaySettingsA entrys but i can't remember exactly..

After all, 640x480 it's really problematic with programs..the better workaround it's configure alternative standalone 15khz resolution and avoid conflicts..640x484, etc.

[scsa187]

I have this same issue on Windows 10. Made a thread about it too but no replies. Only super resolutions work and I also have a 30i and 60i mode both have sync issues.

[mrchrister]

No dice in Windows 10 either. Exact same issue, 640x480 gives a distorted picture. Attached are two screenshots of vm maker and the output on screen at 640x480

[scsa187]

@mrchrister Did you find any fix to this?

[mrchrister]

Thanks for your help guys. Figured out I needed to adjust H FREQ by opening up the PVM. Now 18.5.1 works like a charme!!