NVIDIA Pixel Clock Patcher

[ToastyX]

(12-09-2020 11:30 PM)Margatroid Wrote:  No, I don't need the patcher with the C9, but I do need to use it if I want to still be able to run the other monitor at 120hz. The current patcher breaks the functionality of the C9 and also does not give me 120hz on the Overlord through DisplayPort-to-DVI-D. It always worked in the past on my GTX 970 with DVI-D alone. To be honest, I don't understand what you mean by saying that the patcher does not affect DisplayPort limits. The signal is still having to go through the DVI-D cable, and this Overlord monitor is old enough that 120hz is an "overclock" mode, meaning that the pixel clock patcher along with CRU is the only way 120hz will even show up as an option. Something is wrong... Unless what you're telling me is that DisplayPort is incapable of running 1440 at 120hz without lowered color depth, which seems very unlikely to me. Is DisplayPort really less capable than DVI-D at 1440 120hz? I thought it was a newer technology with greater bandwidth.

In any case, keep in mind that the patcher is giving me blackscreen problems requiring a hardware restart of Windows on the Overlord monitor, not just on the C9 TV. There seems to be some kind of larger compatibility issue with these newest Nvidia drivers.

edit: Okay I just literally have no idea what you're talking about. DisplayPort definitely will do 1440p at 120hz: https://www.cablematters.com/blog/Displa...port-144hz

"You have to keep the pixel clock under 476 MHz, and that's with 6 bpc color. The limit for 8 bpc color is 357 MHz."

Are you talking about HDMI? What is this? I don't get it, man. If the pixel clock patcher isn't necessary to get DisplayPort to run at higher refresh rates, then why will 120hz not show up on under Advanced Display Settings even though I've added it in CRU? Every time I got new drivers in the past and was using DVI-D, I had to use the pixel clock patcher to get 120hz to show up as an option. How else am I going to convince Windows that this monitor can do 120hz?

I'm talking about the adapter. You said you are using an active DisplayPort to dual-link DVI adapter. The video card sees that as a DisplayPort monitor. The patcher doesn't affect DisplayPort limits. DisplayPort is packet-based and runs at fixed link rates, so I can't change the limits like with DVI.

The limit depends on the link rate and number of lanes:
https://www.monitortests.com/blog/common...ck-limits/

Active DisplayPort to dual-link DVI adapters use HBR with 4 lanes, so yes, that adapter is less capable than overclocked dual-link DVI without adapters. You would need a dual-link DVI adapter that supports HBR2 with 4 lanes, which doesn't exist.

With that adapter, you need to keep the pixel clock under 476 MHz for it to work at all, and the color depth is automatically reduced to 6 bpc beyond 357 MHz because there isn't enough bandwidth for 8 bpc with HBR. The people that are getting 2560x1440 @ 120 Hz with that adapter are getting 6 bpc color and not realizing it. DisplayPort monitors that support HBR2 can do 2560x1440 @ 120 Hz without reducing the color depth.