Fatal1ty b450 gaming-itx/ac HDMI problem

[chulleJ]

Hello! I hope this goes here, not in the graphic card forum although it is related both with graphic and motherboard.
I'm using Fatal1ty b450 gaming-itx/ac motherboard with AMD 3400G so no external graphic card. It has both DP 2.1 and HDMI 2.0 ports. I have AOC 24b2xh with HDMI and the ancient VGA. Right now I'm connected with DP to HDMI adapter because I can't use the HDMI port because of a strange issue.
Before this one, I had AOC I2276VW monitor with a DVI-D connector and I bought HDMI to DVI cable. The monitor is in perfect working order because I have been using it on a different PC for 6 years. And everything is good till I start to convert something (media) or render something in Adobe Premiere. Then the monitor just starts to show static, just like in old TVs when there is no signal from an antenna. When I pull HDMI off from the motherboard connector and put it right away back, everything goes back to normal for few seconds, and then the screen goes off again, and so on...
I changed the old monitor with a new AOC 24b2xh monitor. It has an HDMI only and VGA. I connected it, this time with a pure HDMI cable of course. But a similar thing happens again. But this time monitor goes blank for few seconds and comes back again without pulling the cable out. But it goes blank every now and then, on every occasion, not just rendering like before. Interestingly, it goes blank when I do something, for example, when I click something, double-click something, and other random situations too. Worth mentioning: when the picture goes off, the sound via HDMI goes off too because the monitor has 3,5 mm audio out so it is possible to connect the speakers with the monitor and the sound goes via that HDMI. That means that the whole connection goes down and on again. Just like it is physical problem with the connector. But what confuses me is that when the PC is idle, when I do nothing on it, it WILL NOT happen in most cases. I changed two other HDMI cables, the problem persists. I reinstalled Windows twice, the problem persists. I tried lowering the refresh rate to 60Hz, nothing happened. I tried uninstalling the graphic driver and left myself just with Microsoft basic video adapter driver, you can imagine that problem was not solved, of course. Then I bought Display Port to HDMI adapter which can't deliver a 75Hz refresh rate, but those other things DON`T HAPPEN when I connect the monitor to DP, no blank screen anymore. Just without a greater refresh rate, probably because of the adapter itself.
Did you ever have something similar? It reminds me of physical damage in the connector itself but then how to explain that connection breaks just when the PC is not idle and when I click something.
Thank you, everyone! Greetings from Croatia!

 

[thedehumidifier3]

I ran into the same issue with the same motherboard and a 3200G last year when I built it as a HTPC. The only solution I've found while using HDMI is to lower the output pixel format to YCbCr 4:2:0 with 8-bit color. This loses color data, but hasn't been a huge deal for me using it on a large TV for videos.

There's a newer BIOS available for the board (4.40 while I'm on 3.70), which I may try, but I doubt it fixes it. I remember trying a multitude of different things including different versions of drivers and bumping up the SOC voltage slightly, but nothing fixed it.

At least now I know I'm not the only one with the issue.

Edit: Just updated the BIOS to 4.40 and still get HDMI dropouts with higher pixel formats.

 

[chulleJ]

Thanks for replying. I updated BIOS before your reply and also didn't help. Well, I will try your solution just to see will it help in my case although I won't keep it because I need whole color space. I will post the reply after that.

 

[thedehumidifier3]

Sounds good. And yeah, I think your current DP -> HDMI workaround is the best if you're using it as a normal desktop PC and need the full range RGB. Using a DP -> HDMI adapter also solved the problem for me, however then my TV wouldn't auto change to the "Graphics" preset, which I found more annoying than the 4:2:0 downsampling.

Another "solution" is putting in a graphics card, but that kinda defeats the purpose of having a lower power APU based machine.

There must be something a little off with the HDMI 2.0 chip they're using on these motherboards. Maybe I'll ping ASRock support about it. It's not a big enough deal for me to return/replace the board though.

 

[tabascosauz]

Pretty surprised to see both of you reporting this issue, never thought I'd see someone else with these intermittent static/blank screen issues. I don't have the same CPU and board (Ryzen 4650G and B550I Aorus AX, so newer gen APU and board) in my HTPC, my issues were on a 4K60 TV and that TV only. During movie playback it'd start dropping out in exactly the aforementioned ways.

I don't think there is an "HDMI 2.0" chip on the motherboard. Some Intel platforms used to do that. The Ryzen APU handles all the display output just as it handles all of its own I/O on account of being a SoC.

Only working method was to step resolution down to 1080p, not even 1440p60 would work. I'll probably revisit the issue in a couple weeks and see if a new HDMI 2.0/2.1 cable, or a HDMI to DP cable, can change things up.

• I've been through half a dozen different BIOSes on my board from mem OC, no changes. I don't think any of the recent AGESAs have touched any GPU stuff.
• No changes from different Radeon Software versions or configs.
• No changes from pixel formats.
• No changes from VSOC; I already run pretty high VSOC (1.18V) on account of running DDR4-4200 for the iGPU.

Cables are the only thing I can think of really. HDMI cables are the only display cables I've ever had that have sometimes exhibited some problems years down the line.

 

[thedehumidifier3]

Interesting. I guess I forgot to mention in my posts that I've been running 2160p60. I forget if lowering it to 1080p or lowering the framerate fixed the dropouts for me since one of the main reasons I built the HTPC was to have 4K 60fps playback. I definitely tried a number of different cables and switching between going through my AV receiver and directly into the TV to no avail.

Have you tried disabling HDCP in the Radeon Software? I know that's often pointed at for causing HDMI handshaking issues that can manifest as momentary dropouts, but it never solved this problem for me.

And yeah, thanks for the correction about the "HDMI 2.0 chip." You're correct that the SOC handles most of that. I was thinking about an ITE IT66317 HDMI 2.0 re-timer buffer chip that's on these boards. (reference: https://www.tweaktown.com/reviews/8...B450-Gaming-ITX/ac-Circuit-Analysis-Continued)

 

[chulleJ]

I will soon conclude that nothing helps solving the problem. Of course that I can stick to dp to hdmi cable but it's a little annoying that I don't have 75hz using that cable although I can't really notice any significant difference. I already tried to disable HDCP didn't help, changing to 4:4:4 (limited) (only option available beside 444 full) didn't help either.. I'm not planning to put graphic card since I wanted small build..

 

[thedehumidifier3]

That stinks. Radeon Software shows 4:2:2 and 4:2:0 options for me, but it could be those formats are only supported on TVs and not your monitor. The 4:4:4 options give me dropouts like you're experiencing.

The only other thing I can think of is maybe trying a dedicated DP -> HDMI cable (like this: https://www.amazon.com/gp/product/B07PWCNFW7/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) instead of an adapter. Maybe that'll get you 75Hz (I'm assuming that's at 1080p)? I have no proof though, it's just something else to try if you wanted.

 

[MIRTAZAPINE]

All I can think of is probably your hdmi port on your motherboard is damage maybe. I have a problem close to this with a damage hdmi port in my haswell mobo, the screen would go blank after that.

 

[chulleJ]

All I can think of is probably your hdmi port on your motherboard is damage maybe. I have a problem close to this with a damage hdmi port in my haswell mobo, the screen would go blank after that.

Well, I can't rule that out in any way...

That stinks. Radeon Software shows 4:2:2 and 4:2:0 options for me, but it could be those formats are only supported on TVs and not your monitor. The 4:4:4 options give me dropouts like you're experiencing.

The only other thing I can think of is maybe trying a dedicated DP -> HDMI cable (like this: https://www.amazon.com/gp/product/B07PWCNFW7/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) instead of an adapter. Maybe that'll get you 75Hz (I'm assuming that's at 1080p)? I have no proof though, it's just something else to try if you wanted.

Regarding cables, the only thing I didn't try was that. I know that adapter wouldn't give me 75 Hz but I didn't buy the whole DP to HDMI cable. It is 1080p, yes

 

[ixi]

Here with 4650G, B550M DS3H. Using hdmi cable, girlfriend from time to time plays witcher on full hd even though it is connected to sony tv 4K. Have never seen any bugs you guys mentioned prior. Youtube videos and local videos. No problems .

In motherboard specification. Maybe that is why I'm fine.

1 x HDMI port, supporting a maximum resolution of 4096x2160@60 Hz
* Support for HDMI 2.1 version, HDCP 2.3, and HDR

 

[tabascosauz]

Well, I can't rule that out in any way...

Regarding cables, the only thing I didn't try was that. I know that adapter wouldn't give me 75 Hz but I didn't buy the whole DP to HDMI cable. It is 1080p, yes

The reason the adapters don't give >60Hz is because higher refresh rates require a native connection, HDMI to HDMI or DP to DP (IIRC, that's my understanding).

So I don't even know if the cable will do anything >60Hz. The higher end DP to HDMI cables advertise 4K60, but it's just that - they make no claims as to higher refresh rate at lower resolutions. It's the same with the higher end DP to HDMI adapters, they advertise 4K60, and say that you can lower the resolution and maintain 60, but nowhere do they advertise that you can trade resolution for more refresh rate.

Probably best to see if you can get a hold of a new HDMI 2.0 or 2.1 cable. Most of the time you'll hear the same tired adage that "cables matter the least", but I've had more than one occasion where an HDMI 2.0 interface actually needs something better than an ancient HDMI 1.4 cable to run 4K60 properly.

I know I said VSOC didn't seem to work, but APUs generally like VSOC better than CPUs (the latter where >1.1V VSOC is often detrimental to stability). The iGPU still runs off of VSOC, it just splits its own CLDO voltage off of VSOC, so you give it more and it has more to work with. So you could try bumping it a bit, up to the safe limit of 1.2V.

 

[thedehumidifier3]

The reason the adapters don't give >60Hz is because higher refresh rates require a native connection, HDMI to HDMI or DP to DP (IIRC, that's my understanding).

So I don't even know if the cable will do anything >60Hz. The higher end DP to HDMI cables advertise 4K60, but it's just that - they make no claims as to higher refresh rate at lower resolutions. It's the same with the higher end DP to HDMI adapters, they advertise 4K60, and say that you can lower the resolution and maintain 60, but nowhere do they advertise that you can trade resolution for more refresh rate.

Probably best to see if you can get a hold of a new HDMI 2.0 or 2.1 cable. Most of the time you'll hear the same tired adage that "cables matter the least", but I've had more than one occasion where an HDMI 2.0 interface actually needs something better than an ancient HDMI 1.4 cable to run 4K60 properly.

I know I said VSOC didn't seem to work, but APUs generally like VSOC better than CPUs (the latter where >1.1V VSOC is often detrimental to stability). The iGPU still runs off of VSOC, it just splits its own CLDO voltage off of VSOC, so you give it more and it has more to work with. So you could try bumping it a bit, up to the safe limit of 1.2V.

Yeah, you're probably right about the refresh rate. It was just an idea since maybe it'd behave a little differently than an adapter...or maybe not.

Cables do definitely matter with HDMI. I remember the first time I hooked up an UHD Blu Ray player to my 4K TV and was getting white speckles everywhere. I was using some old cable though and once I replaced it with a newer one, all was good. However, I don't think my particular issue with this mobo is cable dependent. I can use the same HDMI cable with a PS4 Pro and get full RGB 4K HDR without dropouts.

I may further play around the SOC voltage later. I think I went up to 1.15V but didn't want to go any further since I'm running that HTPC 24/7 as a little NAS as well. The idea of it being a SOC stability issue can make some sense because it seems like the dropouts occur more when the CPU is doing spurts of activity. But it's inconsistent and hard to prove.

@chulleJ, another random idea: have you tried creating a custom display mode in the Radeon Software and force it to 75Hz while using the DP->HDMI adapter? The idea being that the adapter can support it but Windows/drivers aren't detecting the support.

 

[Liquid Cool]

I owned that motherboard for a year or so with a 2200G, I know it's pretty touchy with cables. Mine would go to a solid color(I can't remember what color though) if it wasn't hooked up perfectly. I ended up replacing the cable and the problem stopped.

I personally have just never had good luck using DP to HDMI cables. I've used these on several business graphics cards with retail monitors...if it wasn't a mystery audio issue cropping up it was something else. Usually...something bizarre.

,

Liquid Cool

 

[thedehumidifier3]

I owned that motherboard for a year or so with a 2200G, I know it's pretty touchy with cables. Mine would go to a solid color(I can't remember what color though) if it wasn't hooked up perfectly. I ended up replacing the cable and the problem stopped.

I personally have just never had good luck using DP to HDMI cables. I've used these on several business graphics cards with retail monitors...if it wasn't a mystery audio issue cropping up it was something else. Usually...something bizarre.

,

Liquid Cool

Good to hear a different cable fixed it for you. What resolution/framerate/pixel format were you running?

A DP->HDMI adapter fixed the dropout issue for me, but it must not pass all the EDID metadata or whatever information the TV needs to identify that a PC is connected so it can use the appropriate picture mode. Basically like you said, adapters can often get you most of the way there but not 100%.

 

[chulleJ]

@chulleJ, another random idea: have you tried creating a custom display mode in the Radeon Software and force it to 75Hz while using the DP->HDMI adapter? The idea being that the adapter can support it but Windows/drivers aren't detecting the support.

@thedehumidifier3 It wouldn't let me save any new mode because it says the display is not compatible with new settings.
If anything I concluded that the problem doesn't occur when I put the refresh rate on 60Hz via HDMI. When putting on 75Hz problems are back. I could mostly agree that problems might be in HDMI cables (although I changed 3 so far) or something related to power/voltage...

 

[chulleJ]

So you could try bumping it a bit, up to the safe limit of 1.2V.

@tabascosauz Just for the record, I also tried this, didn't help. Thanks, everyone for your replies! If I ever solve this I will let you guys know..

 

[Liquid Cool]

Good to hear a different cable fixed it for you. What resolution/framerate/pixel format were you running?

Everything was running stock at 1080p/60Hz on a Dell S2715H.

Best,

Liquid Cool