tl;dr The Samsung KU6290 is a 40" 4K TV for around $300. It has HDMI 2.0, Chroma 4:4:4, input lag of around 35ms, and has been recommended on Amazon for use as a computer monitor. The 6290 is identical to the KU6300 except for the smart remote control.
I've been doing a ton of research on monitors, televisions and display technology. My goal was to purchase a larger display to use for the following tasks:
- General computer use (web browsing, email, etc)
- Programming (mostly using the JetBrains IDEs and Visual Studio
- Word processing
Some of my other goals and constraints
- Inexpensive (sub $500)
- Wall mountable
Initially, I was looking at 27" to 30" monitors, but I discovered that 4K/UHD/3840 × 2160 (all three mean the same thing) medium sized monitors aren't really that useful for productivity, programming, and word processing. The idea is that these tasks are text-intensive, and a 4K resolution on a 27" monitor is going to produce text sizes and UI element sizes that are too small to see comfortably.
Instead, I started looking at a 4K television that I could use as a computer monitor. Based on reports from other people, and on my desk size, it seemed that 40" was about the right size. When looking for a 4K TV-as-monitor, I discovered that there are a few important factors:
Chroma 4-4-4: Chroma when used in reference to televisions refers to algorithms used to compress the RGB color signals. The more compression, the faster the signal can be transmitted and processed. This is fine for video or games, but when you start compressing colors, text can become blurry. Chroma 4-4-4 means that there is no compression. Most of the people I've spoken with have agreed that finding a tv that allows for 4-4-4 chroma is one of the most important factors when using a tv as a monitor.
HDMI 2.0 input: There are two common HDMI standards, 1.4 and 2.0. Only 2.0 will support 4K @ 60Hz. 1.4 will maxes out at 4K @ 30Hz. The Hz refers to the refresh rate of the screen. For programming and general computer use, 30Hz may be fine for most people, but the difference between 30Hz and 60Hz when gaming is very noticeable. Many serious gamers use displays with a 120Hz refresh rate. The higher the rate, the less motion blur there is. This is especially important when the FPS of a game or video increases. In general, you won't notice a big quality difference from 60Hz to 120Hz unless your average FPS is also above 60. Unfortunately, for now, HDMI 2.0 doesn't support a 120Hz refresh rate at 4:4:4 Chroma, as the data bandwidth is too low. You would need either Display Port or USB 3.1 for this. Very few 4K TVs have a display port input, and I haven't found any that have a USB 3.1 video input.
Input Lag: Measured in milliseconds, this is the amount of time it takes before change in the source data is reflected on the screen. This rating is mostly irrelevant for video playback, as once the video starts, the response time doesn't really matter. However, it is very relevant in a monitor for general use, programming, and video games. A high response time will produce a noticeable lag between a mouse movement (or controller movement) and the change on the screen. In competitive, fast paced games like Call of Duty, or DOTA, even a small improvement in input lag can improve a person's ability. As I'm not in the upper echelons of competitive gaming, this isn't a huge factor but is still important. Input lag is inversely correlated with data bandwidth (i.e. chroma).Thus lag can be reduced by increasing chroma compression and using 4:4:4 chroma will produce the highest input lag for a given display. I haven't found any hard rule, but it generally seems that an input lag of under 50ms is good enough for both for general computing and general video gaming. For comparison, higher-end 1080p monitors have around a 15ms input lag. A couple of other points. Many TVs have a "Game Mode" which will reduce input lag at the expense of video or color accuracy. This is an acceptable trade-off for most instances. Since Chroma 4-4-4 is not nearly as important in video games as it is for displaying text and programming, increasing the chroma compression to decrease input lag is a good trade off.
So in summary, I went looking for a 4K television that:
- Between 37" and 43"
- Capable of chroma 4:4:4
- HDMI 2.0
- Relatively low input lag
- Under $500
I looked at a number of options, but ultimately went with the Samsung 40" KU6290 for $300 (2016 holidays). The KU6290 is identical to the more popular 6300 except that is doesn't have the voice activated "smart" remote, and doesn't allow for Bluetooth audio connections. The television has good reviews on Amazon, and a number of people have recommended it for use as a computer monitor. Here is what I like about it
- Multiple chroma levels (including 4:4:4)
- Low input lag
- Multiple modes (gaming, video, etc)
- Lots of customization options. Check out the Amazon reviews for a helpful guide on which values to set for use as a PC monitor.
- Available at a local retailer (Best Buy in my case) for ease of return
- Wall mountable (uses 400mm x 400mm VESA brackets)
This is an entry-level 4K tv, and there are some downsides. First, it has a low response time. Multiple reviewers have said that motion blur is noticeable in high-action movies. Second, the viewing angle is not very good when viewed more than 20 degrees off-center. Third, it can't reproduce as many colors as other TVs and monitors. None of these drawbacks are particularly worrisome for use as a PC monitor. The reduced color space may be an issue for graphic designers, but not for programmers.
Here is the Amazon listing and reviews for the Samsung KU6300
The TV will be arriving next week and I will update my post once I have it configured. I'll be using it with an MSI gaming laptop with a GTX 1070.