2560x1440 60Hz doesn't work over HDMI (Geforce GT 620).

2560x1440 60Hz doesn’t work over HDMI (Geforce GT 620).


I just got a new Dell monitor (U2715H), and even with beta Nvidia driver (355.06) on Debian testing x86_64, it doesn’t detect highest resolution (2560x1440) when connected over HDMI to Geforce GT 620. I got an HDMI 2.0 compliant cable, and according to Dell reps, the monitor should support 2560x1440 over HDMI. Is it a driver issue and is there any way to work around that? See attached nvidia-bug-report.sh log.

nvidia-bug-report.log.gz (77.2 KB)

Some suggested using xrandr to set the video mode explicitly. I tried doing it, and first got a EDID file with nvidia-settings, and run edid-decode. Where is what I got there:

Detailed mode: Clock 241.500 MHz, 597 mm x 336 mm
               2560 2608 2640 2720 hborder 0
               1440 1443 1448 1481 vborder 0
               +hsync -vsync

So I used those values to make a new mode in xrandr:

xrandr --newmode "2560x1440_60.00"  241.50  2560 2608 2640 2720  1440 1443 1448 1481 +hsync -vsync
xrandr --addmode HDMI-0 "2560x1440_60.00"

But I got this error:

X Error of failed request:  BadMatch (invalid parameter attributes)
  Major opcode of failed request:  140 (RANDR)
  Minor opcode of failed request:  18 (RRAddOutputMode)
  Serial number of failed request:  31
  Current serial number in output stream:  32

Any idea what can be wrong?