Follow-up on 4K displays for programmers

4K is so not for programmers.

Today's cheap 4K displays are not up to snuff. All of those pixels do not compensate for mousing at 30 frames per second and it doesn't matter if you have millions of pixels if the colors are all wrong. So we returned our Seiki 4K televisions and switched back to our trusty 19-inch ViewSonic monitors. Some of us took the 4K televisions home and installed them in our living rooms, where 4K rightfully belongs.

Just kidding.

We're not crazy. 4K is for programmers, not couch potatoes.

There are serious weaknesses with the current batch of 4K displays, from the still-not-available HDMI 2 specification, to shortsighted design and marketing decisions such as targeting the living room first. These limitations are not a matter of technology, making them acutely frustrating to an informed buyer. We should not suffer these failings; we should not be beta-testers for a clueless industry.

Still, the cost-benefit analysis is all too simple: the cost is low, and the benefit is high, despite the failings.

I was told that multiple internets (is Internet2 still a thing?) would enjoy a follow-up to my earlier post. So here it is.

Some of the Seiki televisions in our office

Would we do it again?

Having used these displays for about two months, do we have any regrets?

No. We'd buy them today had we not already bought them in January. The price is simply too low and our need for an upgrade was too high to hesitate. With luck, superior displays will hit the market this year. But instead of waiting, we're happy to have huge displays right now.

As for weaknesses, two months have confirmed some that were known and uncovered some others.

30 frames per second sucks

The principal weakness of today's 4K displays is the use of HDMI 1.4, which is limited to 30 frames per second at 3840x2160. The marketing material for the Seiki television is a bit confusing. The box prominently says "120Hz," which is in fact available at low resolutions. But at the maximum resolution of 3840x2160—the resolution you are going to use if you connect this television to your computer—HDMI 1.4 limits refreshes to 30 per second ("30Hz").

It's important to understand that 30Hz on an LCD is nothing like 30Hz from a strobe light or a CRT. 30 frame updates are sent to the monitor per second, but there is no flicker. The screen is not going dark between frames. Still, with so few frames per second, routine computer user interface mechanics such as aiming with a mouse pointer or scrolling a window can be choppy and frustrating.

Let me be clear: 30 frames per second sucks. All of my colleagues and I would prefer displays with 60 frames per second or better, all else being equal. But all else is not equal, which means that while 30 frames per second is more bothersome to some than others, we all tolerate it.

I'm optimistic that affordable displays with HDMI 2 or modern DisplayPort inputs will arrive soon, along with the necessary GPUs. 4K at 60Hz will be even more compelling than today's options.

But do I want to postpone working with this many pixels to save $500? No thanks.

The colors aren't just bad, they are broken

If you've looked into low-cost 4K televisions such as the Seiki, you're probably aware of ample criticism about the color accuracy and limited adjustments of these displays. While a firmware patch mercifully grants backlight dimming, the best we can achieve in color calibration is disappointing to anyone who uses the phrase "color calibration." You know who you are.

Weak color accuracy is just the start. The Seiki has a defect in how it processes some bitmaps. Certain pixel configurations cause bizarre rendering failures. The defect can be seen in gradients, for instance on blogs with gradient backgrounds (who would make such a thing?).

The following composition compares the Seiki (left) displaying a background gradient from this blog, the same gradient displayed on a Dell U3011 (middle), and the source bitmap (right).

Comparison of Seiki and Dell displays rendering a gradient

At first I suspected a bizarre interoperability failure between the display driver and the browsers' gradient algorithm, but this effect is observed even in a screenshot. The defect is not in the bitmap itself; it's simply how the Seiki television displays the bitmap.

But here's the thing. Take a look at how awful the color accuracy is for programming. Again, Seiki at left; Dell U3011 in middle; and zoomed bitmap at right.

Comparison of Seiki and Dell displays rendering source code in an editor

Oh wait a second, that's not too bad. I can actually read the code at the left.

In most cases, the defect is subtle. For a web developer, this defect can be annoying but as a known defect, it's not particularly hurtful to productivity. (Note that our workstations also have small secondary monitors that can be useful when absolutely necessary to confirm such artifacts are not our fault.)

This defect sucks. Do I want a display that doesn't do this? Yes. Do I want my money back and a smaller display? No.

Sleep mode is completely wrong

If you have secondary monitors, do not allow your Seiki to go to sleep unless you have a good window manager. From the computer's perspective, when the Seiki is asleep or off, it is disconnected. Power off your Seiki, and your computer will move all of your applications to your other monitor. Power it back on, and you've got a new empty workspace.

There are hardware workarounds for this behavior, but none we have been able to verify. Our preferred workaround is software: use either a tiling window manager or a window manager that allows you to save and restore window positions. Just press a hotkey after powering up the Seiki and you're back to work.

As I mentioned previously, the display also doesn't wake up via DPMS. This is a bit annoying, but ultimately it's merely inconvenient to have to press the power button.

An odd bit: at my house, I have an old Panasonic plasma in my living room that behaves like a monitor (it has DPMS support and no speakers) and meanwhile on the desktop, we have a Seiki television with speakers but no DPMS.

Miscellaneous problems

A few other minor problems:

  • The on-board audio capability is a bit flaky. Most of us aren't using the speakers, but those who have say that the volume level is sometimes unresponsive (fixed at mute, for example) until they reboot their PC. This might be a problem with the nVidia HDMI audio though. We have not investigated this.
  • We have not yet captured the detailed steps to get Linux working at 3840x2160 on our hardware. We needed to set up a new workstation recently and it took several hours and caused great anguish, suffering, and maybe even cursing. The Mac OS X and Windows folks have had no issues and use this as cause to laugh at the Linux users.
  • The factory settings have an unsharp mask enabled. As Chris Cardinal points out below in the comments, that default is unfit for a computer display since it wreaks havoc with text and everything else. I would never even enable such a filter on a television, so this default is plain bad regardless of context. Adjust the "Sharpness" setting to zero to yield an unfiltered view.
  • I am a total noob at blogging for fame and cash monies, so I did not have the Amazon link wired up for mad referral loots. I've since fixed it, too late of course.
  • Seiki never contacted me to offer early access to 60Hz 4K models. And that has been my ulterior motive all along!

The good stuff

3840x2160. Period. Full stop. Enough said. But I'll elaborate.

3840x2160 is so good that it significantly outweighs the downsides above and even potential downsides we've not yet encountered, such as unknown long-term reliability. We have about twenty of these displays and none were dead on arrival. Most have no dead pixels, but a few have a small number.

We don't have any scientific or pseudo-scientific measure of the displays' bearing on our productivity. All we have are anecdotes. And anecdotally, none of us would switch back to a small monitor. Mouse lag caused by the 30Hz refresh rate is our chief complaint, but none consider it worse than the alternative: less display.

Some quotes from colleagues:

  • “As expected, I don't really care about the not-great color accuracy.”
  • “As expected, I do care about the not-great color accuracy. Although, since I don't do photo processing here, I don't care as much.”
  • “Mouse lag at 30Hz is still annoying.”
  • “Mouse lag is annoying, but it became more tolerable than I expected. I would not go back. I miss this display when I use my home computer.”
  • “Mouse lag would be a bit less annoying if windows had slightly larger grab areas on their edges.”
  • “Try a tiling window manager.”
  • “I'm using Windows.”
  • “Get a real OS.”

Overall, we strongly feel the Seikis have been a productivity boost. This may be dismissed as a placebo, but on the other hand, perhaps greater screen real estate genuinely increases programmer productivity. If nothing else, it appears to increase programmer happiness and that probably translates to productivity somewhere down the line.

Worth it.

Still, if you have an 8K display I can install on my desktop, drop me a line. I'm serious. Very serious. 8K serious. Those Internet2 guys probably have 8K displays. Curse them and their Internet2.
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