HDMI to DVI adapter causes blurry text on external monitor

[rviertel]

I am running Ubuntu 16.04. My laptop is a Dell inspiron 15-3521 and it only has an HDMI output. No DisplayPort, DVI, VGA, etc. I purchased an HDMI to DVI adapter cable to connect my laptop to an external HPZR30w monitor that only has DisplayPort and DVI. The text on the external monitor is very blurry/pixelated.

The output of xrandr is

Screen 0: minimum 8 x 8, current 2646 x 808, maximum 32767 x 32767
LVDS1 connected primary 1366x768+0+40 (normal left inverted right x axis y axis) 344mm x 193mm
1366x768 60.01*+
1360x768 59.80 59.96
1280x720 60.00
1024x768 60.00
1024x576 60.00
960x540 60.00
800x600 60.32 56.25
864x486 60.00
640x480 59.94
720x405 60.00
680x384 60.00
640x360 60.00
DP1 disconnected (normal left inverted right x axis y axis)
HDMI1 connected 1280x800+1366+0 (normal left inverted right x axis y axis) 641mm x 400mm
1280x800 59.91*
VGA1 disconnected (normal left inverted right x axis y axis)
VIRTUAL1 disconnected (normal left inverted right x axis y axis)
As you can see I only have one resolution mode to try on the external monitor. I tried adding other modes as described here

Can't set a higher screen resolution in a external display in a Dell Mini 10v laptop

but when switched to that mode in the display settings the external monitor just went black.

Here is the output of lspci

00:00.0 Host bridge: Intel Corporation 3rd Gen Core processor DRAM Controller (rev 09)
00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09)
00:14.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller (rev 04)
00:16.0 Communication controller: Intel Corporation 7 Series/C210 Series Chipset Family MEI Controller #1 (rev 04)
00:1a.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #2 (rev 04)
00:1b.0 Audio device: Intel Corporation 7 Series/C210 Series Chipset Family High Definition Audio Controller (rev 04)
00:1c.0 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 1 (rev c4)
00:1c.1 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 2 (rev c4)
00:1d.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #1 (rev 04)
00:1f.0 ISA bridge: Intel Corporation HM76 Express Chipset LPC Controller (rev 04)
00:1f.2 SATA controller: Intel Corporation 7 Series Chipset Family 6-port SATA Controller [AHCI mode] (rev 04)
00:1f.3 SMBus: Intel Corporation 7 Series/C210 Series Chipset Family SMBus Controller (rev 04)
01:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101/2/6E PCI Express Fast/Gigabit Ethernet controller (rev 05)
02:00.0 Network controller: Qualcomm Atheros AR9485 Wireless Network Adapter (rev 01)

Any suggestions on how I can get a sharp image?

 

[rviertel]

Turns out this is because the monitor requires a "DVI-D Dual Link" connection. I had standard DVI and it wasn't able to support a better resolution

 

[Natsukage]

Turns out this is because the monitor requires a "DVI-D Dual Link" connection. I had standard DVI and it wasn't able to support a better resolution

Yes, this monitor has a 2560 x 1600 resolution. DVI cannot render this with a single link.