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Results: Viewing Angles and Uniformity

Overlord Tempest X270OC, 27" 120 Hz IPS Gaming Monitor Review

The more monitors we test, the more we can see that off-axis viewing performance is dependent not only on pixel structure (IPS, PLS, TN, etc.) but the backlight technology as well. And we can see that the anti-glare layer makes a difference too.

Since we couldn’t use the AccuPel, we replaced our Windows desktop with a gray step pattern. You can see the clear advantage that IPS technology enjoys compared to the other TN-based ones we've reviewed. The view from 45 degrees to the side only shows a little light falloff and no color shift. From above (also 45 degrees), there is a tendency toward green and red, depending on the brightness level. Overall though, you won’t find off-axis image quality like this on any high-refresh TN display.

Screen Uniformity: Luminance

To measure screen uniformity, zero and 100-percent full-field patterns are used, and nine points are sampled. First, we establish a baseline measurement at the center of each screen. Then the surrounding eight points are measured. Their values get expressed as a percentage of the baseline, either above or below. This number is averaged.

It is important to remember that we only test the review sample each vendor sends us. Other examples of the same monitor can measure differently.

First up is black field uniformity.

One of the biggest complaints about entry-level IPS displays is poor black field uniformity, better known on Internet forums as light bleed. Happily, our sample does not suffer from this malady. In fact, it looks just as good as any other monitor we’ve tested, regardless of price. Measurements show slightly hotter zones across the bottom of the screen.

Here’s the white field result:

A measurement of 3.71 percent means the Tempest has near-perfect white uniformity. We couldn’t see any areas that were brighter or dimmer than the rest.

Screen Uniformity: Color

To measure color uniformity, we display an 80-percent white field and measure the Delta E error of the same nine points on the screen. Then we simply subtract the lowest value from the highest to arrive at the result. A smaller number means a display is more uniform. Any value below three means a variation that is invisible to the naked eye.

Although the X270OC finishes last in our test group, its color deviation across the screen is still invisible. To see good quality-control at such a low price gives us hope that IPS monitors will all become less expensive soon.

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  • 1 Hide
    oudmaster , July 17, 2014 12:54 AM
    the price is interesting with these specs !
    any idea if there will be a similar monitor spec but 4k resolution ?

  • -5 Hide
    oudmaster , July 17, 2014 12:54 AM
    the price is interesting with these specs !
    any idea if there will be a similar monitor spec but 4k resolution ?

  • -3 Hide
    oudmaster , July 17, 2014 12:55 AM

  • 4 Hide
    wtfxxxgp , July 17, 2014 2:08 AM
    Crickey me...this is a monitor of note it seems! At that price point, I find it incredible. Well done to Overlord! The only issue I have now is... will the price increase as a result of all the buzz this will generate? This is probably going to be my next monitor, depending on exchange rates...
  • -5 Hide
    Shneiky , July 17, 2014 2:12 AM
    4K at 120 MHz? Not in the next 5 years.
  • 2 Hide
    Swiperd3 , July 17, 2014 3:23 AM
    Driving QHD to 120 FPS at the max graphics detail is sure as hell will require A LOT of horsepower. Will TOP-SLI/CF-x2 be enough for modern FPS games?
  • 1 Hide
    Traciatim , July 17, 2014 4:04 AM
    Wow, you get this with one of the variable sync techs and you have yourself one fantastic monitor.
  • 0 Hide
    waxdart , July 17, 2014 4:11 AM
    16:9 :( 
  • 5 Hide
    envy14tpe , July 17, 2014 4:37 AM
    Thank you Thank you Thank you. I've been dying to see a review on this monitor.
  • 1 Hide
    Reaver192 , July 17, 2014 4:44 AM
    Yeah, I've been waiting fir this for too long. I wanted one of these months ago but they have been out of stock. Such a sweet deal
  • 5 Hide
    avatar_raq , July 17, 2014 5:27 AM
    This is the holy grail of PC monitors, if only it comes with 120 Hz guaranteed out of the box.
  • 2 Hide
    yogalD , July 17, 2014 5:34 AM
    I wish it had a strobe backlight though, that would make it perfect
  • 5 Hide
    Durandul , July 17, 2014 6:17 AM
    If it had an option for Display port, that would have been almost perfect. That being said, I use DVI anyway, so who am I to complain.
  • 2 Hide
    MonsterCookie , July 17, 2014 6:50 AM
    This is already a step at the good direction. Even the price in $ looks decent.
    Question is how much will this cost here in Europe.

    Also, now make the same thing happen in a 30" format with 2560x1600 resolution, and than I am definitely opening my wallet.
  • 2 Hide
    mapesdhs , July 17, 2014 7:14 AM

    MonsterCookie, alas I doubt that will happen. A few years ago, 1440 and 1600
    height monitors were priced basically the same, ie. expensive. Back then, top-end
    GPU reviews tended to use 2560x1600 as a typical max res test for gaming. But
    then buying patterns evolved, the usual feedback between pricing and demand,
    people tended to opt more and more for 1440 displays instead. As a result, when
    I wanted to get a 1600 IPS a while ago, I was amazed to find 1600 hieght displays
    were about 4X more expensive than 1440 IPS models.

    Presumably it suits the industry to home in on a more typical standard, and for
    the moment, beyond HD, 2560x1440 seems to be it. Very unlikely the industry has
    any interest in pushing 1600 height to the masses, so probably the next main step
    up will be to 4K, or as I wish they'd call it instead, quad-HD.


  • 1 Hide
    ubercake , July 17, 2014 7:14 AM
    The specs look goood, but the key is they don't guarantee 120Hz for all OC monitors:

    It's like hoping you'll get an i7 that will have a stable OC to 4.5Ghz 24/7. It's the luck of the draw.
    I don't much like putting my money on hope. If they did have a guarantee or just sold a monitor that shipped to my house with 120Hz capability, I'd be more likely to hand over my cash.

    You know darn well they make sure the review site is getting a good one.
  • 1 Hide
    daglesj , July 17, 2014 7:29 AM
    So does it work fine at say 90Hz and if so is that an improvement?
  • 1 Hide
    npyrhone , July 17, 2014 7:42 AM
    Thanks a million for the review! This will be next monitor. Hallelujah! Lacking a decent non-TN gaming panel, I've played with a pro 24" CRT for all these years.
  • 2 Hide
    npyrhone , July 17, 2014 7:46 AM
    A few answers and corrections concerning ideas thrown around in this thread:

    1) Yes, This works perfectly at 90Hz. Yes, it is a great improvement. Much greater improvement is 60->90 than 90->120.

    2) All monitors are from this day to the future to come 16:9. So, its useless to fancy 16:10 monitors anymore, they wont be coming ever again.

    3) 4K 120Hz gaming monitors wont be coming, either. At least not in the foreseeable future.

    4) Overclocking this is not luck of the draw. They all come at least 96Hz, and the great majority work 120Hz.

    5) The lack of displayport etc is what helps keeping input lag low.
  • 9 Hide
    rishiswaz , July 17, 2014 8:11 AM
    I wonder why they don't just have another model with cherry-picked panels that they ship at 120 out of the box
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