VEGA 64 Displayport 1.2 Limited Monitor Output Issue

[Bhuvsta]

Hello all,

I bought a Vega 64 from OCUK in November and I've been having problems from Day 1 getting it to display at my monitors native resolution - 2160p60. If I set my monitor to Displayport 1.1 there are no issues acheiving 2160p30. However when I set my monitor to Displayport 1.2 I get several issues depending on which driver I have installed (I've tried a selection from 17.12.1 to 18.11.12):

17.12.1 - Limited to 1080p60 at DP1.2 (but 2160p30 at DP1.1) with the "The System has detected a link failure....." message.

18.3.1, 18.3.4 and 18.6.1 - Limited to 1080p60 at DP1.2 (but 2160p30 at DP1.1) but NO 'link failure' message.

18.7.1 and 18.9.3 - Limited to 1080p60 at DP1.2 (but 2160p30 at DP1.1) but NO 'link failure' message. These drivers actually have 2160p60 (and many other resolutions above 1080p60) but they all result in a blank screen and the display reverts to 2160p60.

18.11.12 to latest - Get a blank screen during driver install, which I assume is the drivers defaulting to 2160p60 without falling back to 1080p60.


I've tried a fresh install of Windows 10 but the problem still persists. Without an AMD graphics driver installed Windows defaults to 3840 x 2160 @ 64fps which appears to work ok.

There were no issues when I connected my PC to a UHD TV via HDMI 2.0. The PC successfully played a few games so I can assume that it's not a power consumption/supply issue. Unfortunately my monitor is limited to HDMI 1.4.

I was previously using a Sapphire R9 290 Tri-X with the same hardware and that had no issues with attaining 2160p60 using DP1.2 so I don't think it is an issue with the Displayport cable I'm using. I have tried Displayport cables of different lengths and even a DP to mini-DP cable.

I would be grateful for suggestions?


Mobo: Asus B350-F Strix (Latest BIOS)

CPU: AMD Ryzen 1600 (Default Speed)

RAM: 16GB 3400 Mhz DDR4

Graphics: Sapphire Vega 64 Nitro+

Monitor: Phillips BDM4065

OS: Windows 10

PSU: EVGA G2 1kW

 

[Participant]

When you're setting res with the AMD drivers installed, does the behaviour change between setting the res using Windows vs. using the AMD control panel?

I have that monitor with a GTX970 and have no issue getting 2160p@60 over DP1.2.

 

[Bhuvsta]

Thanks for the quick reply!

As far as I can tell, the modern AMD control panels doesn't actually have the ability to set resolutions or refresh rates and I have been doing it throught Windows. The AMD control panel does however have the ability to create custom resolutions. I've created a custom resoution at 2160p@60 but the monitor remains at 1080p60 when I try to use it.

I've also just noticed that the "Link Speed" reported by the AMD control panel at DP1.2 is 5.4 Gbps (either 1 x 5.4 Gbps or 2 x 2.7 Gbps depending on cable used). When using DP1.1 (at 2160p30) is reaches 10.8 Gbps (4 x 2.7 Gbps). UPDATE: "Link Speed" appears to change depending on which resolution and refresh rate you select so doesn't appear to be an indicator of anything.

 

[Participant]

Wonder if it's a bandwidth issue - check it's not set to 10 bit colour maybe?

 

[Participant]

Just found this thread:

https://community.amd.com/thread/219681

Sounds like there are some fudges but no definitive solution. RMA?

 

[Bhuvsta]

I've tried both 6-bit and 8-bit and it made no difference. Thanks for your help! I will have a look through that thread and then RMA if nothing works.

 

[Participant]

I've tried both 6-bit and 8-bit and it made no difference. Thanks for your help! I will have a look through that thread and then RMA if nothing works.

Only other thought is maybe try a different brand of DP cable. It's a bit of a punt and shouldn't be necessary, but may be worth a try if you've so far used one 'brand' of cable.