GoKawiilThe Philips Evnia 27M2N5500XD is the first 1440p 500Hz LCD gaming monitor to hit our desk. Yes, we know, not exactly a great monitor name. It's right up there with the worst. But this is a genuinely interesting monitor, as it pushes LCD refresh rates into territory we haven't experienced before. It also raises an interesting question: can IPS LCD technology actually support this sort of refresh rate?
The 27M2N5500XD is a classic 27-inch 2560 x 1440 IPS LCD monitor with relatively standard gaming specifications. There's adaptive sync variable refresh rate support, no real HDR capability since it lacks proper local dimming, and a rated 1ms gray-to-gray response time.
The new feature here is the 500Hz refresh rate at 1440p, which can be pushed to 540Hz through an overclocking mode. But it doesn't stop there. This monitor also has Dual Mode support, which increases the refresh rate to a whopping 1,000Hz at a resolution of 1280 x 720.
That makes it the highest refresh rate monitor we've ever tested, beating some of the latest 1440p dual-mode WOLEDs. Those monitors also hit 540Hz at 1440p, but are limited to 720Hz in the 720p dual-mode configuration. Despite OLEDs generally being much faster in response times, it's actually LCDs that reached the 1,000Hz mark first.
Philips isn't lying about the capabilities of this product: it does hit 1,000Hz in the 720p mode, and it does hit 540Hz in the 1440p mode with overclocking enabled. There's no trickery here. But going into this review, we weren't really concerned about whether the LCD panel could technically update the image 1,000 times per second. What we were actually concerned about is whether this panel's response time performance would be fast enough to properly support that refresh rate.
With LCDs, OLEDs, and all other sample-and-hold displays, great motion quality doesn't come from refresh rate alone. That's certainly part of the equation: higher refresh rates mean the screen is updated more frequently, reducing certain types of blur, increasing smoothness, and reducing input delay.
But fast response times are also required. If the screen can't respond and update the image quickly enough, it won't be able to keep up with the refresh rate, leading to blur and artifacts such as ghosting. The two factors, refresh rate and response times, go hand in hand.
The crucial thing we look for on a high refresh rate display is whether the screen can complete most of its transition from one color to another within the time between refreshes. This is a good measure of whether response times are bottlenecking the refresh rate.
If the screen can't actually finish changing before another refresh occurs, it won't ever properly show the image. It's kind of like asking someone to switch to a new task before finishing the one they were already working on. In monitor terms, doing this creates blur and hurts motion quality.
So when testing this Philips monitor, one of the key things we're looking for is average response times that are fast enough to enable a 1,000Hz refresh rate. At 1,000Hz, there's a new refresh every 1ms. That's the refresh window, so ideally we want to see average initial response times faster than 1ms, a truly difficult task for LCDs.
... continue reading