A couple of years ago a relative who uses a Linux workstation I support bought a 4K (4096*2160 resolution) monitor. That meant that I had to get 4K working, which was 2 years of pain for me and probably not enough benefit for them to justify it. Recently I had the opportunity to buy some 4K monitors at a low enough price that it didn’t make sense to refuse so I got to experience it myself.
The Need for 4K
I’m getting older and my vision is decreasing as expected. I recently got new glasses and got a pair of reading glasses as a reduced ability to change focus is common as you get older. Unfortunately I made a mistake when requesting the focus distance for the reading glasses and they work well for phones, tablets, and books but not for laptops and desktop computers. Now I have the option of either spending a moderate amount of money to buy a new pair of reading glasses or just dealing with the fact that laptop/desktop use isn’t going to be as good until the next time I need new glasses (sometime 2021).
I like having lots of terminal windows on my desktop. For common tasks I might need a few terminals open at a time and if I get interrupted in a task I like to leave the terminal windows for it open so I can easily go back to it. Having more 80*25 terminal windows on screen increases my productivity. My previous monitor was 2560*1440 which for years had allowed me to have a 4*4 array of non-overlapping terminal windows as well as another 8 or 9 overlapping ones if I needed more. 16 terminals allows me to ssh to lots of systems and edit lots of files in vi. Earlier this year I had found it difficult to read the font size that previously worked well for me so I had to use a larger font that meant that only 3*3 terminals would fit on my screen. Going from 16 non-overlapping windows and an optional 8 overlapping to 9 non-overlapping and an optional 6 overlapping is a significant difference. I could get a second monitor, and I won’t rule out doing so at some future time. But it’s not ideal.
When I got a 4K monitor working properly I found that I could go back to a smaller font that allowed 16 non overlapping windows. So I got a real benefit from a 4K monitor!
Video Hardware
Version 1.0 of HDMI released in 2002 only supports 1920*1080 (FullHD) resolution. Version 1.3 released in 2006 supported 2560*1440. Most of my collection of PCIe video cards have a maximum resolution of 1920*1080 in HDMI, so it seems that they only support HDMI 1.2 or earlier. When investigating this I wondered what version of PCIe they were using, the command “dmidecode |grep PCI” gives that information, seems that at least one PCIe video card supports PCIe 2 (released in 2007) but not HDMI 1.3 (released in 2006).
Many video cards in my collection support 2560*1440 with DVI but only 1920*1080 with HDMI. As 4K monitors don’t support DVI input that meant that when initially using a 4K monitor I was running in 1920*1080 instead of 2560*1440 with my old monitor.
I found that one of my old video cards supported 4K resolution, it has a NVidia GT630 chipset (here’s the page with specifications for that chipset [1]). It seems that because I have a video card with 2G of RAM I have the “Keplar” variant which supports 4K resolution. I got the video card in question because it uses PCIe*8 and I had a workstation that only had PCIe*8 slots and I didn’t feel like cutting a card down to size (which is apparently possible but not recommended), it is also fanless (quiet) which is handy if you don’t need a lot of GPU power.
A couple of months ago I checked the cheap video cards at my favourite computer store (MSY) and all the cheap ones didn’t support 4K resolution. Now it seems that all the video cards they sell could support 4K, by “could” I mean that a Google search of the chipset says that it’s possible but of course some surrounding chips could fail to support it.
The GT630 card is great for text, but the combination of it with a i5-2500 CPU (rating 6353 according to cpubenchmark.net [3]) doesn’t allow playing Netflix full-screen and on 1920*1080 videos scaled to full-screen sometimes gets mplayer messages about the CPU being too slow. I don’t know how much of this is due to the CPU and how much is due to the graphics hardware.
When trying the same system with an ATI Radeon R7 260X/360 graphics card (16* PCIe and draws enough power to need a separate connection to the PSU) the Netflix playback appears better but mplayer seems no better.
I guess I need a new PC to play 1920*1080 video scaled to full-screen on a 4K monitor. No idea what hardware will be needed to play actual 4K video. Comments offering suggestions in this regard will be appreciated.
Software Configuration
For GNOME apps (which you will probably run even if like me you use KDE for your desktop) you need to run commands like the following to scale menus etc:
gsettings set org.gnome.settings-daemon.plugins.xsettings overrides "[{'Gdk/WindowScalingFactor', <2>}]" gsettings set org.gnome.desktop.interface scaling-factor 2
For KDE run the System Settings app, go to Display and Monitor, then go to Displays and Scale Display to scale things.
The Arch Linux Wiki page on HiDPI [2] is good for information on how to make apps work with high DPI (or regular screens for people with poor vision).
Conclusion
4K displays are still rather painful, both in hardware and software configuration. For serious computer use it’s worth the hassle, but it doesn’t seem to be good for general use yet. 2560*1440 is pretty good and works with much more hardware and requires hardly any software configuration.