Additional Screen Lag Information: Updated 2013-07-17----------------------------------The screen lag at 4k & 30Hz appears to be caused by the Radeon video card because at 30Hz and 1080p, there is no noticeable lag. If I get a chance to try an Nivida card, I will update the results.Power Saving Issue Resolved: Updated 2013-07-17----------------------------The TV has a service mode which can be entered by MENU 0000.In the factory Serivce mode under OTHER -> POWER ON MODETurning that on fixes my issues with power saving. I plug the TV into the "Switched" ported on my UPS (uninterruptable power supply). My UPS has an energy saving feature. When my computer goes into STANDBY, the switched ports on the UPS turn off automatically and the TV plugged into it thus turns off.The factory setting allows the TV to turn on automatically when the TV gets AC power, which is what happens when my computer comes out of standby.Also in the factory service mode, I was able to turn the backlight down from 100 to 70. This reduced the power from 79W down to about 55W. More importantly, it allows me to set the user brightness controls at 50 which provides the best grayscale reproduction!I later found out the backlight setting doesn't get saved through a power cycle so it doesn't help much.Summary: UPDATED 2013-07-13--------It works well as a computer monitor except that it lacks proper power management for day-to-day use. Overall I am however impressed by the value. It's is insane how anyone can sell a 4k monitor at this price range. I'd recommend it to anyone needing more real estate for computer programming and general computer usage. It does not make a good 1080p TV however.UPDATED 2013-07-13:I've found a couple of fixes that reduce lag enough that makes it suitable for FPS:1. When running At 4k resolution, turn VSYNC off. (Yes, you'll see some tearing, but it's way better than having the lag.)2. Run at 1080p @ 60 Hz or higher.If you're like me, you might be wondering "what's the catch?" How can anyone sell a 39" 4k monitor at prices below just about all 30" 2560x1600 monitors out there? Well, I have NO IDEA how they are doing it, but there' no catch here. It's the real deal and this monitor has superb value.Pros----+ Large, 38.5" diagonal+ 4k resolution is AMAZING+ Bright+ no dead pixels, no stuck pixels+ Color looks good+ Very low cost+ Compatible with Radeon HD6000 series+ has reasonable speakers+ multiple input sources+ includes a TV tuner (which I don't use)+ USB reader for media (music + pictures, I also do not use this feature)Cons:------ Lack of power management- Uneven brightness across screen- 1080p doesn't look good- For FPS gaming, must run with VSYNC off at 4k resolution to reduce/eliminate lag.Decision: 39" or 50"?----------------------Seiki has both a 39" (actual is 38.5) and a 50". Which one is a better choice? I feel the 39" is the better choice. Ultimately, the size of the screen affects viewing distance. (Read on for more details)A reason to get the 39" is if your desk isn't big enough. Another reason to get the 39" is the price differential. $700 vs $1000. The 50" is essentially 40% more money, but has almost 69% more surface area. (Note that additional surface area is not necessarily useful as it's not an increase in pixel count.)Viewing differences: In terms of aesthetics, the 39" looks like a monster on my desk, so I'm guessing the 50" would look ridiculous. To get the maximum benefits of the higher resolution, I have placed the monitor approximately 20" from my eyes. Depending on how I'm sitting, that distance can increase to about 30". That's the approximate range of distances at which I like to view this monitor. I have noticed one negative about viewing such a large, flat, screen from such a close distance: at 20" viewing distance, the corners of the screen are effectively viewed at angles of approximately 50 degrees. This makes the content at the edges a bit less comfortable for viewing due to he extreme angle. The monitor stand is not adjustable. It sits a bit low for me. If I raise the monitor up about 5"o that my eyes are at the same height as the center of the screen, I can reduce the corner viewing angles to about 44 degrees.If I move the monitor back, the viewing angles become less extreme, but the pixels looks smaller such that the benefits of the 4k resolution are slightly negated.I had a brief moment of "buyer's remorse" when I though the 50" would have allowed me to set the monitor back further and thus reduce the extreme viewing angles, but when I calculated the difference in viewing angles with the larger monitor, I realized that it would not have made any difference to perceived viewing angles. Since the 50" is wider, I'd have to set it back to a viewing position of 26" (30% more) to get the same viewing angles as my 39". If I set it back 6" more inches, then the effective pixel size also gets smaller. In other words, there no real benefit in terms of viewing angle with getting a bigger monitor, however, the larger monitor does allow an increase viewing distance, which may be beneficial if there are multiple viewers of the screen.In terms of DPI (dots per inch) or dot density, the 39" has 114 DPI. (The 50" has 88DPI.) As a relative comparison, the 39" monitor's DPI is the same as a 1080p monitor with a 19.25" diagonal. The 50" monitor's DPI is equivalent to a 1080p monitor that is 25" in diagonal.For me, I upgraded from two 20" LCDs (100 DPI) and the Seiki 39" does have noticeable smaller pixels (at 114DPI). Also note that with multiple monitors, I can turn the monitors at an angle and form an arch so the viewing angle for each monitor is less extreme.Video Card Compatibility------------------------This monitor does not have a DisplayPort. It uses HDMI. The maximum framerate at 4k resolution is 30Hz. Before I bought the Seiki, I searched all over the internet to see if my current video card, a Radeon HD 6870-512MB, would drive this monitor. I could not find any conclusive information, and furthermore, a spec sheet from AMD indicated the HD7000 series supported 4k monitors, but the HD6000 series did not. I ended up ordering a HD7870, but it's still in transit. To my surprise, the HD6870 works perfectly with Seiki. It fired right up when I connected the monitor. I didn't have to adjust any settings on either the TV or PC for it to work. I didn't even reboot my computer. I just put the computer into standby, switched monitors, then woke the computer from sleep.I have noticed that while my computer is booting, while it's in the BIOS screen, the monitor will display nothing at times. It's inconsistent between boots. Sometimes, parts of the bios screen will show, other times, the screen will remain black until the Windows logo.(As a side note, if you plan to get a new video card for this monitor, Windows 8.1 is reportedly supporting OpenCL which the Radeons are 2x as fast as Nvidia, for the same price point.)Gaming ** UPDATED. LAG ISSUES RESOLVED **-------I will start by saying that I have a steam account and while I game occasionally, it's not high on my priority list. In terms of speed, the monitor is about on par with other 1080p monitors. However, put the resolution to 4k and there's noticeable lag if VYSNC is enabled. Disable VSYNC and everything is quite reasonable. Originally, I had a lot of lag at 1080p, but I think it was because I had "ALLOW GPU SCALING" turned on in the Catalyst Control Center.Some older DirectX games have trouble running at 4k resolution. For example, it took me a while to get Rise Of Nations to run at 3840. Dungeon Siege would not run at 4k. Most of the newer titles run fine at 4k (albeit the lag.)I also notice the lag when watching videos within a browser at 4k resolution. The audio leads the video ever so slightly if I'm using the audio of the sound card instead of the HDMI audio out.TV--I don't watch much TV; I don't even have cable or disk. As a test, I did switch my computer to 1080p resolution to test the image and the desktop looks terrible compared to a standard 1080p monitor. I'm guessing the same would occur with TV/video usage. If the main purpose is for TV watching, I'd highly recommend you get a regular 1080p set for now. 4k content is not mainstream. 1080p doesn't look good on this monitor.Picture & Color---------------The monitor does have a little bit of uneven brightness, but for application use it's not noticeable. I've attached a picture to show the variation on a grey image, but due to the exposure, I'd say it's much more exaggerated than what I see sitting in front of it.Colors look fine to me, but I'm not doing any calibrated photo work to scrutinize the color. Photos look great in my opinion.I created a series of native resolution images to check for dead pixels. Images include white, black, red, green, blue, and then four corresponding checked patterns for each color: 2 black/color checkered, 2 white/colored checkered, at even and odd pixels spacings. I found NO DEAD PIXELS or NO STUCK PIXELS EITHER! AMAZING that I couldn't even find one defect out of over 8M pixels.Settings--------For computer usage, I suggest setting the video card to RGB 4:4:4 LIMITED (rather than FULL). On a grey-scale gradient, it allows a better range of color display from full black to full white with more shades of grey in-between.For the monitor, turn off sharpness and noise reduction.Complaints----------I have one other gripe with this monitor, and that is with the power management, or lack thereof. I'm not sure how long I'd have to leave the monitor on before it'll go into power saving mode, but there is a possibility that this unit has to be turned off manually. Unlike a normal computer monitor, this unit does not go into standby when the computer is turned off nor does it "wake up" automatically when the computer is turned on. The monitor must be powered on and off manually.Conclusions-----------I'm reasonably satisfied with this purchase. If Seiki could figure out how to fix the power management, this would be a perfect monitor. Given the price, I'm giving this one a 5-star recommendation due to the impressive value.