[SOLVED] Monitor Not Supporting Advertised Refresh Rate

QUICKSILV3R15

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May 30, 2016
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I recently upgraded to the AOC AGON AG493UCX2. I'm having some issues getting the advertised 165hz on the monitor. I'm using a VESA verified DisplayPort 1.4 cable connected to RTX 2080 super. Both in Windows settings and Nvidia control panel, I'm capped at 5120x1440@120hz. Any ideas on how I can fix this? Thanks.
PS. NVIDIA Control Panel does not allow any higher refresh rates with overclocking.

Pc Specs (For Reference)
OS: Windows 11 Home
CPU: AMD R7 5800x
RAM: 32GB DDR5 3333mHz
GPU: Nvidia GeForce RTX 2080 Super
 

Zerk2012

Titan
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I recently upgraded to the AOC AGON AG493UCX2. I'm having some issues getting the advertised 165hz on the monitor. I'm using a VESA verified DisplayPort 1.4 cable connected to RTX 2080 super. Both in Windows settings and Nvidia control panel, I'm capped at 5120x1440@120hz. Any ideas on how I can fix this? Thanks.
PS. NVIDIA Control Panel does not allow any higher refresh rates with overclocking.

Pc Specs (For Reference)
OS: Windows 11 Home
CPU: AMD R7 5800x
RAM: 32GB DDR5 3333mHz
GPU: Nvidia GeForce RTX 2080 Super
That monitor is so close to 4K that 120 is probably all it can do with DP 1.4
 
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QUICKSILV3R15

Honorable
May 30, 2016
20
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I'm not sure if my calculation are correct, but it looks to me that to push out that amount of pixels you need GPU with DP 2.0, while yours has only 1.4.

Your response was the lead I needed to figure this out. My findings are detailed below.


[TLDR:] Not enough bandwidth.


DisplayPort 1.4 max bandwidth is: 32.4 Gbps.

This means anything higher than 32.4 Gbps will require a higher DisplayPort standard such as DP 2.0

The following bandwidth calculations are based on 8-bit panels

5120x1440@120Hz bandwidth is: 26.54 Gbps
5120x1440@165Hz
bandwidth is: 36.5 Gbps
3840x2160@144Hz
bandwidth is: 35.83 Gbps


The monitor I asked about in my original post is the AOC AG493UCX2 is a 10-bit panel. 4K will be included once again for reference.


The following bandwidth calculations are based on 10-bit panels

5120x1440@120Hz bandwidth is: 31.85 Gbps
5120x1440@165Hz
bandwidth is: 43.79 Gbps
3840x2160@144Hz
bandwidth is: 43.00 Gbps


Resource used for calculations: Bandwidth calculator - Kramer Electronics (kramerav.com)
 
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