Custom Resolution Utility (CRU)

[falkentyne]

(10-10-2015 06:32 PM)ToastyX Wrote:  

(10-08-2015 11:58 PM)falkentyne Wrote:  is it possible (or even feasible) to make a patch to bypass the displayport limits, or at least to extend the pixel clock range for 8 bits per channel color, or is this not possible?

It might be possible, but I haven't found a way to do it. The DisplayPort limits are not constants like the other limits, so it would be very difficult to figure out what code needs to be changed.

DVI, HDMI, and VGA are constant streams of data with the pixel clock determining the data rate, so I can just change the limits. DisplayPort is packet-based with fixed clock speeds, so I'm not sure how overclocking would work.

I see. Thank you.

A bit unrelated, but I had been doing some overclocking. Got my XL2720Z to 2560x1440 at *115hz*. This was only possible with bizarre HT:

2560x1440
Porch 48/3
Sync 32/5
HT: 2641 (any lower and values turn red)
VT: 1497 (1496=black screen). Only VT 1497-1502 work.
Refresh rate: 115hz.
Pixel clock: 454.67 MHz
(displayport. 6 bpc).
Tried DVI once 120hz...monitor switched to VGA input right away).

1 more hz higher (116hz) and I start to get flickering pixels.
120hz has too much corruption yet there is no frameskipping at all...image is perfectly smooth, just flickering pixels

Do you think 115hz is stable/safe even though I don't see any "obvious" flickering? Maybe theres very random flickering, cant tell for sure. No frameskipping.

Any lower on the VT and I get a black screen/out of range message with no display.

Since the lowest valid VT for this is 1449 (black screen/out of range), I'm assuming this VT range that works (1497-1502) only works because this is (im guessing) reserved internally for Lightboost mode for reducing strobe crosstalk (even though 1138, 1143 and 1149 tell the monitor to enter 3d mode). There's no other explanation as to why this VT range works, and everything from 1400-1495 gives an out of range error (from testing VT's at 1920x1080). Note VT 1370-1400 show an image but the OSD says "out of range" anyway and most VT's have frameskipping in this range. (the scaler resolution shows 1792x1344 in that VT range :/)