Custom Resolution Utility (CRU)

[ToastyX]

(02-03-2018 01:45 PM)wood1y Wrote:  Do you think it is possible to run 3440x1440@100Hz on Dual-link DVI?

Yes, but that doesn't mean the monitor will support it, regardless of what the manual says.

[ToastyX]

(02-01-2018 04:55 AM)CRTFTW Wrote:  Anyway, I've run into a strange problem where Radeon GPU's on Windows PC's are running into artificial resolution limits in the driver, and they're ignoring overrides above this limit in CRU, and enforcing the same limit in AMD custom resolution tool. Basically, it seems to be looking at the max resolution or pixel clock on the EDID, and limiting the custom resolutions to near that maximum. Resolutions from CRU just won't show up, they're ignored and not selectable

Like when I hook up a Dell P992 (max resolution on EDID is 1600x1200@85hz, max horizontal scan 107kHz) I can't pick resolutions much higher than 2048x1536. But when I use my larger LaCie monitor, where 2048x1536@85hz is the max in the EDID, I can create resolutions with horizontal width around 2700 pixels, like 2736x2054@60hz.

I need to know the exact limits you're hitting to figure out what's going on, and I need the EDID for the Dell as well. Common DisplayPort limits are 300/400 MHz, 360/480 MHz, and 600 MHz.

[CRTFTW]

(02-03-2018 02:00 PM)ToastyX Wrote:  I need to know the exact limits you're hitting to figure out what's going on, and I need the EDID for the Dell as well. Common DisplayPort limits are 300/400 MHz, 360/480 MHz, and 600 MHz.

Ok, I tested some more and found that the issue is that there is some arbitrary pixel clock limit set by the driver, and it is based off the EDID it's reading from displayport in some way.

I tested by moving in 1Hz increments in vertical sync at various resolutions. I found that the Dell P992 is being limited at ~330mHz, the LaCie is being limited to ~530mHz, and the 4k dummy plug, ironically, has the lowest limit at 280mHz.

Notice that in the EDID's, the Dell is labeled as 240mhz max, the LaCie at 420mHz max, and the 4k dummy has no entry. So it's hard to glean any sort of algorithm AMD might be applying here. Those values might have nothing to do with it.

Dell EDID is posted below.

[ToastyX]

(02-04-2018 12:58 AM)CRTFTW Wrote:  I tested by moving in 1Hz increments in vertical sync at various resolutions. I found that the Dell P992 is being limited at ~330mHz, the LaCie is being limited to ~530mHz, and the 4k dummy plug, ironically, has the lowest limit at 280mHz.

Those numbers don't make sense, so it can't be a pixel clock limit. I haven't seen this sort of behavior before. Maybe it's listening to the kHz range limit. Have you tried including the range limits and changing the ranges? I don't see what else could be limiting it.

[CRTFTW]

(02-04-2018 03:04 AM)ToastyX Wrote:  Those numbers don't make sense, so it can't be a pixel clock limit. I haven't seen this sort of behavior before. Maybe it's listening to the kHz range limit. Have you tried including the range limits and changing the ranges? I don't see what else could be limiting it.

I did the incremental 1Hz test on multiple resolutions, and resolutions would always start being ignored at the same pixel clock for the specific monitor. Maybe the drivers are basing the max pixel clock of something other than what is found in "display properties/range limits"

But I'll give the horizontal limit idea a try, since like pixel clock it is a thing that is increasing with resolution/refresh rate.

And I also wonder if this could be a side effect of the displaport MST/SST standard that is tripping up the drivers, since this adapter is meant to be used in that way. But like I said, AMD's Ubuntu drivers don't have this issue, so it's definitely an artificial, maybe unintentional limit.

I guess my last resort would be to reprogram that HDMI dummy to give me better results, but I need to figure out what I would need to put in the new EDID. Well, that and I don't know of any software updated in the last 10 years for overwriting EDID's. All I can find on the net is Powerstrip, and some DOS-based tool.

[ToastyX]

(02-04-2018 05:58 AM)CRTFTW Wrote:  And I also wonder if this could be a side effect of the displaport MST/SST standard that is tripping up the drivers, since this adapter is meant to be used in that way. But like I said, AMD's Ubuntu drivers don't have this issue, so it's definitely an artificial, maybe unintentional limit.

That may be the case. I don't know how the driver determines how much bandwidth to assign per connection. There used to be a diagnostic page that would show you this information: http://support.amd.com/en-us/kb-articles...yPort.aspx

[CRTFTW]

Increased the horizontal scan max in CRU, made no difference. Hitting the same 530mHz ceiling on the LaCie.

[gsoul5005]

Is it possible to enable freeSync through eDP on a laptop?

I have got a HP x360 with Ryzen 2500U.

Will importing EDID info from another FreeSync display through CRU work?

[ToastyX]

(02-05-2018 11:39 AM)gsoul5005 Wrote:  Is it possible to enable freeSync through eDP on a laptop?

I have got a HP x360 with Ryzen 2500U.

Will importing EDID info from another FreeSync display through CRU work?

No.

[caenlen]

@Toastyx

I just ordered the new AMD 2400G Raven Ridge APU, will I still be able to use Toastyx Cru and AMD Patcher with this new setup on my QNIX 27" 1440p panel, I normally OC it from 60hz to 110hz, but thats only using normal setups, not sure if these new APU's are supported or not with your tools.