Wasabi Mango UHD420 42-in 4K - FreeSync and HDMI 2.0 for $800

Manufacturer: Wasabi Mango


A few years ago, we took our first look at the inexpensive 27" 1440p monitors which were starting to flood the market via eBay sellers located in Korea. These monitors proved to be immensely popular and largely credited for moving a large number of gamers past 1080p.

However, in the past few months we have seen a new trend from some of these same Korean monitor manufacturers. Just like the Seiki Pro SM40UNP 40" 4K display that we took a look at a few weeks ago, the new trend is large 4K monitors.

Built around a 42-in LG AH-IPS panel, the Wasabi Mango UHD420 is an impressive display. Inclusion of HDMI 2.0 and DisplayPort 1.2 allow you to achieve 4K at a full 60Hz and 4:4:4 color gamut. At a cost of just under $800 on Amazon, this is an incredibly appealing value.

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Whether or not the UHD420 is a TV or a monitor is actually quite the tossup. The lack of a tuner
might initially lead you to believe it's not a TV. Inclusion of a DisplayPort connector, and USB 3.0 hub might make you believe it's a monitor, but it's bundled with a remote control (entirely in Korean). In reality, this display could really be used for either use case (unless you use OTA tuning), and really starts to blur the lines between a "dumb" TV and a monitor. You'll also find VESA 400x400mm mounting holes on this display for easy wall mounting.

Continue reading our overview of the Wasabi Mango UHD420 4K HDMI 2.0 FreeSync Display!!

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One of the most interesting things about the UHD420 came in July in the form of a firmware update enabling AMD's FreeSync technology. While the only mention of this update was posted to the support page on the Wasabi Mango support site (entirely in Korean), we decided to order one of these monitors and give it a shot.

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First we gave the HDMI 2.0 functionality a shot while hooked up to a GTX 980Ti. Right out of the box we saw a full 60Hz implementation with 4:4:4 chroma subsampling. Proper HDMI 2.0 support means this could be a great display to use with a HTPC or something like the NVIDIA SHIELD.

Upgrading the firmware was surprisingly easy for this display. After opening the zip file downloaded from the support site, you are presented with a .bin file. Transferring this .bin file to an empty, FAT32 formatted flash drive allows you to update the monitor.

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With the monitor off, plug in the thumb drive to the "Service USB" port, which is specifically labeled on the back of the display. After turning the display back on, the power LED indicator on the button of the display will begin to blink between green and red. Once the light remains solid green, it's time to remove the thumb drive.

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You'll need to hard power reset the display by unplugging it and plugging it back in, but once you do, you'll find the firmware upgraded and a new option for FreeSync in the OSD.

After enabling the FreeSync option in the OSD, the Catalyst Control Center should prompt you that a FreeSync display has been connected, and allow you to enable the feature.

We managed to do all of this successfully, and started to investigate how well this implementation of FreeSync worked with our AMD R9 Fury X. From our testing, we can say that the UHD420 has an variable refresh range of 42-60Hz.

While this may not seem like a lot, it has some utility with a 4K display. By having an extra "cushion" of 18Hz, you can still try to tune game settings to achieve 60Hz for most gameplay, but if the frame rate drops a bit due to a lot of action on the screen, you'll still maintain a smooth experience. However, if you drop below 42 FPS, whatever VSync settings you have set will kick in.

Editor's Note: I wanted to drop in here real fast and talk about my gaming experiences on this monitor. The truth is that gaming on a 4K monitor, regardless of physical size, requires a LOT of GPU horsepower, and this works in favor of the limited variable refresh window implemented on the UHD420. The 60 Hz limit is common to basically all 4K displays on the market today and a VRR / FreeSync range of only 18 Hz would initially seem useless. But with modern GPU hardware capabilities to render at 4K being limited, even in multi-GPU configurations, this slight advantage of tear-free and stutter-free gaming can impact the overall experience a lot. I would hope that gamers would set in-game quality settings in an attempt to hit near 60 FPS all the time, and then allow the 18 Hz VRR window below 60 FPS to act as the buffer or "safety zone." Gamers using 4K monitors will very likely see spikes down in frame rate so this advantage is noteworthy. 

In our time messing around with the Wasabi Mango UHD420 this FreeSync window was definitely taken advantage of. When I did come across a scenario where we dropped below 42 FPS, the experience was poor, to say the least. I still don't like the transition between FreeSync VRR and standard V-Sync modes and prefer what G-Sync does (enabling variable refresh with no bottom limit). The  UHD420 isn't a perfect monitor, but it's unique combination of resolution, variable refresh and pure pixel count is unique in the market.

End Editor's Note

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After doing a bit of digging, we also found that the Wasabi Mango claims compatibility with this same firmware for the UHD550 55-in display. Crossover, another Korean monitor manufacturer, also has released a firmware for the 494K 49-in display, and promises it will come to the 434K 43-in model.

As a word of caution, if you pick up one of these displays make sure it's labeled as the HDMI 2.0 version. Earlier versions of this monitor are not compatible with the FreeSync upgrade.

So this leaves us asking why these particular, generic monitors upgradeable to FreeSync? I have a feeling this has a lot to do with the fact that these Korean companies are doing no customization to the OSD/scaler as a cost-saving measure. Even the popup warnings of things like a device not being connected feature the MStar branding, which is a leading scaler manufacturer. Because they are doing little to no customization, as MStar developed a firmware for the existing silicon, Wasabi Mango and Crossover were able to push them out quickly to consumers.

Even though it doesn't have a very large FreeSync range, it's still extremely cool to see an already existing display be updated with this technology. If you are interested in a large 4K display and have a AMD GPU that supports FreeSync, these monitors are pretty unbeatable for the price.

July 29, 2015 | 06:34 PM - Posted by Anonymous (not verified)

LG 49UB8500 - 4K@60hz, IPS, Passive 3D, IPS, 4:4:4 Chroma, IPS, Web OS, IPS, under $1000. Amazing Computer Monitor.

September 10, 2015 | 01:16 AM - Posted by Anonymous (not verified)

Passive 3D? Could you, or someone who knows elaborate on this? Thank you in advance.

March 15, 2016 | 03:35 PM - Posted by Anonymous (not verified)

I have had the 49UB8500 as a monitor for 6 months and I can say its ok as a monitor, not that great though, you can actually see the horizontal scan lines on the screen which is incredibly annoying to me, the scan lines are their for the 3d feature. The best things going for that tv are very low input lag when running native 4k in game mode and good viewing angle, but I recently upgraded to the samsung 50ju6500 and this tv is quite amazing, has full led backlit array and everything about it is far superior to the 49UB8500 EXCEPT for viewing angle, viewing angle is quite bad on the samsung but when you are positioned in front of the tv it blows everything else I have tried out of the water, that includes 34" ultrawide monitors and 28" 4k monitors

Just thought I would throw a couple pennies in

July 29, 2015 | 06:44 PM - Posted by Edmond (not verified)

Quite a bit better than the 60-60 range all other 40inch monitors have.

July 29, 2015 | 06:57 PM - Posted by DieHard (not verified)

Ryan, it would be great if you would start mentioning that almost all GCN Radeon cards now have access to Frame Rate Target Control.

This is important for Freesync because users can limit the max framerate and the game can always remain in the Freesync "sweet spot".

July 29, 2015 | 07:03 PM - Posted by Anonymous (not verified)

How hard can it be for you guys to buy a colorimeter and start measuring color accuracy, contrast ratio, panel uniformity for all these displays you get your hands on lately???

July 30, 2015 | 07:20 AM - Posted by Skogen (not verified)

Bro's got a point. Any serious tech site should do monitor reviews better than this upstart-YouTube level.

July 29, 2015 | 07:07 PM - Posted by rl (not verified)

Hey Ryan, please be so kind and do a follow up on the other FreeSync monitors (Acer and LG). Supposedly they got a firmware update as well or at least a later batch got one.

The LG is supposed have working OD with FS and also the VRR window is claimed to have been lowered from 48 to 40 Hz.


July 30, 2015 | 05:48 AM - Posted by Mac (not verified)

That's an interesting development, do you have a source for this information? I'm surprised acer,lg and amd aren't crowing about this.

July 30, 2015 | 03:56 PM - Posted by DieHard (not verified)

Source? How about changelog for 15.7 driver :)

Catalyst 15.7 WHQL driver has extended use of FRTC [and AMD's virtual super resolution] to the almost every GCN card.

July 30, 2015 | 03:58 PM - Posted by DieHard (not verified)

Nevermind mac, reading fail. I though you were asking me.

July 29, 2015 | 08:31 PM - Posted by

I am looking for a large format monitor like this one or maybe the seiki one that you reviewed a little while ago. I have found myself watching a lot more video and my existing monitor is not cutting it. So I would like one that does video really well and is good for gaming. Most of the games I play are mmo's so I am not that picky about some things that would drive other gamers crazy. I do not have the horsepower to play in 4k but and probably going to upgrade my video card soon.


July 30, 2015 | 12:33 AM - Posted by Anonymous (not verified)

OTA TV? Not a problem. My HTPC has a Hauppauge tuner card however I might want to add a discrete GPU card since the Ivy Bridge integrated graphics might not keep up and I don't have HDMI 2.0 or the latest DisplayPort output on my old ASUS motherboard. Anyway it would probably be an upgrade over the Dell 19" CRT monitor I watch TV on...I've never paid money on any display-only hand me downs.

July 30, 2015 | 01:12 AM - Posted by Master Chen (not verified)

According to TFT Central, this is a pretty crappy panel, in all actuality. The color levels and calibration are quite bad, and response timings are outright HORRENDOUS.

July 30, 2015 | 02:29 AM - Posted by Anonymous (not verified)

What are you talking about? The only Wasabi Mango I see reviewed at TFT Central is the Wasabi Mango QHD275 Universal model. A different panel. Pay attention!

July 30, 2015 | 03:46 AM - Posted by Master Chen (not verified)

Isn't this the same one? If those are two different models, then I do apologize for the misunderstanding.

July 30, 2015 | 10:07 AM - Posted by Anonymous (not verified)

COMPLETELY different panel. 27" 2560x1440 display, not 42" 4K.

July 30, 2015 | 03:32 AM - Posted by JohnGR

Freesync everywhere.

And 42-60Hz is not bad. People just have to change their mentality. We have learn all this time to put everything at ultra and accept deep drops to even under 30fps just so we have ultra in our settings. Well, that mentality sells more hi end cards, and is the reason for SLI/CF systems. That's why it is promoted so hard. Freesync tells you to be more practical, more logical. Target that 60fps and try to have settings, even if you have to put some settings at high/medium, that will not drop the frame rate under 40fps.

And yes, Ryan, Frame Rate Target Control. You should start mentioning it. PCPer plays Allyn's game, where as a hardcore Nvidia fanboy will try to pass the message that 25fps on a GSync monitor offer the same smooth experience as REAL 50fps. Well, take a video at 15fps, double it's frames and frame rate at 30fps with a video tool and compare it with a real 30fps video. Is it as smooth as the real thing?

July 30, 2015 | 03:46 AM - Posted by the laser it burns

Wow, tempting. Great story. Any chance we could get comments on the rest of the experience of the monitor? How is the build quality? Any of the overdrive issues as with the BenQ? PWM flicker? Warranty?

July 30, 2015 | 10:54 AM - Posted by Anonymous (not verified)

It seems Wasabi Mango just announced a 65" version of this monitor in Korea, with 3D and soundbar support.

Also some people found an unannounced and smaller 49" version on a Korea online store.

I believe they may soon be available through those Korean EBay retailers....

July 30, 2015 | 01:05 PM - Posted by JohnGR

49" mentions Freesync in the specs.

July 30, 2015 | 02:53 PM - Posted by Anonymous (not verified)

It says on this review the HDMI 2.0 model wall mount is 400x400 but on newegg it says the HDMI 2.0 model has a 200x200 wall mount so which one is it?

July 31, 2015 | 08:37 AM - Posted by Anonymous (not verified)

Hey Ryan,
I am not going to use a monitor for gaming so all this stuff about Freesync is nice but not the most important to me. What is critical since I want to be able connect it to the upcoming Ultra HD BlueRay players in addition to media players that will be outputting video signals that are not only 4K but will be decoding source MetaData so it can show DolbyVision high dynamic range. Movies will be incredible. In order to do this those HDMI 2.0 ports must be the latest version that can handle 18 GB/sec not the slower 10.2 GB/sec. Some people are calling the 18 GB version HDMI 2.0"a". So Ryan could you please measure the bandwith speed of Wasabi Mango's HDMI 2.0 imputs and tell us?

August 4, 2015 | 01:02 AM - Posted by Ty (not verified)

is hdmi 2.0 capable of hdr at all? Even with the full 18gbps?

I thought not.

In any event, I'm virtually certain these current korean off brands won't have that. That seems reserved to some of the higher end tv panels of the sort you see samsung making, and again, I think the hdr content comes through the internet not over hdmi 2.0 due to bandwidth issues.

August 1, 2015 | 10:05 PM - Posted by RobHu (not verified)

Any information about color accuracy?

August 2, 2015 | 11:26 PM - Posted by Blehhh (not verified)

is Crossover 434k better than wasabi mango UHD 420
they are both identical price. but which have lower input lag for gaming ? which is a better monitor for gaming ?

August 3, 2015 | 02:47 PM - Posted by Riddick (not verified)

I accidentally got the HDMI 1.4 version and didn't even know about the updated model so I'm shit out of luck, will likely need to palm this off for peanuts in the future unless someone figures out some hack (apparently the older model can't even be updated! period).

In all honestly I think Freesync needs to go down as low as 30hz-60hz range, apparently there is little reason why it can't do it, so hopefully someone figures it out and modifies it in the firmware of these monitors.

August 4, 2015 | 10:59 AM - Posted by Torsoreaper (not verified)

Other than freesync, not sure why this would be better than the curved 40" samsung 4k monitor which is $750 from a reputable company and has significantly more people following it and writing up about it so I would say it has more resources for support if someone needs it.

August 4, 2015 | 01:51 PM - Posted by Anonymous (not verified)

- 120Hz PWM
- No DP 1.2, only HDMI
- 4:4:2 in Game mode, the only one with acceptable input lag

August 4, 2015 | 10:54 PM - Posted by Blehhh (not verified)

Sry not sure about tv and monitor it seems the same thing.
which samsung r u talking about the 750 ?
and what is 120hz PWN ?

August 9, 2015 | 10:57 PM - Posted by Shirley Dulcey (not verified)

There is also a potential use for FreeSync, even with that limited range, in home theater setups. If there is ever a home video release of 48fps high frame rate movies like The Hobbit trilogy, the display will be capable of presenting it correctly.

August 22, 2015 | 08:29 AM - Posted by Anonymous (not verified)

there seems to be so many different versions of this wasabi mango UHD 420....there is a SE version there is a real 4k version and the companies inkorea grade the monitor based on the pixel guarrantee company sells the same monitor at two or three different prices based on pixel count ot dead pixel company gives free shipping for the lower pixel count and charges for shipping for the 100 percent perfect pixel count ...all i wanted to know is which version is the very best quality one...i need the hdmi2 and display port 1.2 and usb 3 and free sync upgrade but how do i know which one i will get...if anyone can tell me the exact model number that will get me all this id appreciate before my purchase

October 9, 2015 | 01:52 AM - Posted by Thanos (not verified)

I recently purchased this monitor I couldn't be happier that I did. Well worth the money. My only issue is how to change the language from korean to english (I spent the first half hour that I had this thing trying to figure out how to change the input source from DP to HDMI 2.0) Can you guys give me a little bit of a walk-through on this? Thanks.

October 16, 2015 | 03:16 AM - Posted by Maggie and Vincent (not verified)

It seems the Freesync firmware is no longer on the WM support website. Can anyone please post it or send it to me ?



February 23, 2016 | 06:11 PM - Posted by Anonymous (not verified)

is this Monitor supports PBP? Picture by picture

March 15, 2016 | 08:09 AM - Posted by Yamcha (not verified)

Yeah, it supports Picture in Picture and picture by picture. I have the UHD400 and am able to use my docked Lenovo in a box on the monitor. Friggin awesome!

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