Dell UltraSharp 40 5K IPS Black 120Hz Monitor Review: It’s A Stunner

Dell's 40-Inch IPS Black Curved Monitor Is A Workstation Pro's High Resolution Dream

dell ultrasharp 40 curved ips black thunderbolt monitor

Dell UltraSharp 40 Curved Thunderbolt Hub Monitor U4025QW: MSRP $1919, Currently $1489
The Dell UltraSharp 40 U4025QW is a big, beautiful, curved Thunderbolt-enabled monitor featuring a 5K2K resolution and IPS Black panel technology. It's ideal for creators and productivity workers who need excellent color fidelity and a ton of high resolution screen real estate.


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  • IPS Black With Great Contrast And Saturation
  • Excellent Color Accuracy
  • 120Hz Refresh Rate
  • Wide Viewing Angles
  • Drop-Down Integrated Thunderbolt Hub
  • Integrated KVM And Tons Of IO Options
  • Great Ergonomics
  • Low Blue Light Eye Care
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  • Slow Response Time For A 120Hz Panel
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We've taken a look at IPS Black panel technology here at HotHardware a few times in the past. This new LG-developed display technology is what enables the Dell UltraSharp 40 Curved Thunderbolt U4025QW monitor we have teed up for review today. We took a look at the 34-inch UltraSharp 34, a 34-inch curved 1440p version, not long ago and were impressed, though some of us were left wanting more. 

More is usually always better, right? So say hello to the Dell UltraSharp 40 Curved Thunderbolt monitor, model U4025QW, sporting 40-inches of curved 5Kx2K high resolution love with a 120Hz refresh rate. Is this thing too big to take in on a workstation desk when you're a foot and a half away from it? Do you really need all that screen real estate? Just how good is IPS Black really, and is this display capable of high accuracy color reproduction for true workstation use? Can you game on this big beauty?

We'll try to answer all those questions and more, as we pixel peep every square millimeter of this exciting, large, cutting-edge desktop monitor from Dell. Let's take a look...

Dell UltraSharp 40 Curved Thunderbolt Hub Monitor U4025QW Specs And Features


What Exactly Is IPS Black Display Technology?

IPS Black is a non-traditional panel technology and underneath its TFT LCD screen and anti-glare coating lurks a display technology that turns traditional IPS on its head. Merck and LG Display teamed-up to bring something truly unique to the table with the IPS Black panel that Dell employs onboard the UltraSharp 40. What sets this apart isn’t just a tweak to the liquid crystal material; it's a fundamental shift in how the panel operates. Traditional IPS displays worked on a "normally off" mode—meaning when no voltage was applied, you'd see a black pixel. But with IPS Black, it's the opposite. No drive voltage? You’re looking at a white pixel instead. Kinda crazy right?

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The result is that IPS Black takes legacy IPS display performance to the next level, offering significantly deeper black levels and improved contrast ratios over traditional IPS panels. The result is a much more accurate depiction of dark areas in an image, all while retaining wide viewing angles and offering even better color precision versus standard IPS displays. It's a solid step forward in delivering more vivid, accurate visuals, and it beats just about anything short of an OLED monitor, without suffering the challenges that technology presents (in terms of burn-in risk, etc.). The Dell UltraSharp 40 specifically can render 99% of the DCI-P3 and Display P3 color space on average, so if you're in need of true color fidelity, this monitor can deliver it. More on this in our testing below.

There are some caveats with IPS Black, however. The only real drawback currently is that, due to the new panel material and reversed voltage modes, response times with IPS Black displays aren't quite as good as standard IPS displays yet, especially IPS gaming monitors. That said, at its Fast mode setting, the Dell UltraSharp 40 can hit a 5ms response time at 120Hz, which is good enough for casual to moderately-fast gaming requirements. Perhaps fast twitch eSports gamers shouldn't apply here, but more on this later. 

Dell UltraSharp 40 Curved Thunderbolt Hub Monitor (U4025QW) Design And Features 

Sprinkled among the deep tech specs above, like the panel's crispy-tight 140ppi pixel density and sharp 2000:1 contrast ratio, you'll notice this panel is a veritable Swiss army knife of a monitor, with copious features and an elegant, not too pronounced 2500R curvature.

dell ultrasharp 40 curved base view
dell ultrasharp 40 curved full back view

The UltraSharp 40's stand has a cable management slot, along with support for tilt, swivel and height adjustment. There's a silver-gray, matte finish with a high density plastic construction over an interior metal frame. As you can see above, the back righthand side of the display is where the power button and on-screen control button reside. It's a pretty standard Dell setup that looks clean and works well, with extremely good flexibility in positioning for optimal ergonomics and viewing. 

dell ultrasharp 40 curved back ports view
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Dell UltraSharp 40 U4025QW IO Port Options

When it comes to connectivity options, this new professional grade Dell monitor really shines. There's a Thunderbolt upstream port that supports 140W Extended Power Range charging for PCs and other devices. That port will drop to 90 Watts, however, if the device only supports SPR or Standard Power Range. There's also another 15 Watt Thunderbolt 4 downstream port for daisy-chaining multiple panels if you're a real estate hog, and a USB Type-C upstream port, supporting SuperSpeed USB 10 Gbps, USB 3.2 Gen 2. You also get the obligatory DisplayPort 1.4 port and an HDMI 2.1 port as well for input options. Then the list goes on with three USB Type-A downstream ports (SuperSpeed USB 10 Gbps, USB 3.2 Gen 2), a single USB Type-A downstream port (SuperSpeed 10 Gbps, USB 3.2 Gen 2), and a 2.5GbE RJ45 Ethernet port with PXE boot, Mac Address pass-thru and Wake on LAN features.

Essentially, you can use this monitor as a true docking station as well.

quick access ports dell ultrasharp 40

And if that wasn't enough, on the above pop-out IO block, you get another two USB Type-C downstream ports (SuperSpeed USB 10 Gbps, USB 3.2 Gen2) with power charging (15W), and a USB Type-A downstream port (SuperSpeed USB 10 Gbps, USB 3.2 Gen 2) with BC1.2 power charging. Dell also packs in a pair of speakers with the UltraSharp 40, in a 2x9 Watt config, that produces decent though uninspiring sound. It'll suffice for office work and conference calls, but high fidelity audio media consumption should likely be handled externally. In any event, all in, the Dell UltraSharp 40 is well equipped with IO and connectivity options galore.

dell ultrasharp 40 curved on screen controls
On-Screen Display Menu

The Dell UltraSharp 40's display settings are straightforward to access, thanks to a conveniently placed joystick on the rear right of the panel. A quick press pops up a menu packed with a ton of options. One of the standout features here is the built-in Network KVM switch, which lets you run two systems off a single monitor with a split display. And if that wasn’t enough, you’ve got Picture-in-Picture and Picture-by-Picture modes on tap, all seamlessly integrated with the Auto-KVM and Network KVM functionality. This large monitor also has Internal Multi-Stream Transport, so you can split the display into two virtual 2560x2160 monitors, without the need for any external software or a DisplayPort splitter. This is definitely a solid set of features for productivity workers and content creation professionals that need to multitask in a big way.

There are also a bunch of controls for preset color space settings, brightness, contrast, etc. However, though the panel arrived pre-calibrated out of the box from Dell, we'd highly recommend setting up this massive high res display with a proper colorimeter calibration first and foremost. 

Speaking of which, let's dig into what we found with our meters and in experiential testing...

Dell UltraSharp 40 U4025QW Color Accuracy, Uniformity And Gamut Coverage Results

We started testing with a couple useful tools, including DisplayCAL calibration and characterization software and a Calibrite Display Plus HL display calibration device. We highly recommend this colorimeter, for users who need top color fidelity and accuracy, as a great tool to get things dialed in.

u4025qw curved ips black color gamut coverage
u4025qw curve ips black color gamut test
UltraSharp 40 U4025QW DCI-P3 Gamut Coverage

Dell claims Delta E is less than 2 on average, and our testing proved an excellent result of 0.11 on average with a maximum shift of 2.77. Gamut coverage is also very good, with near 99.9% sRBG coverage and 94.5% actual measured coverage of the DCI P3 color gamut. The gamut plot, aka the chromaticity diagram, above also visualized this color accuracy result of the Dell UltraSharp 40, which is excellent. 

dell ultrasharp 40 curved IPS black monitor color uniformity test
UltraSharp 40 U4025QW Color Uniformity Test Results

Our color uniformity testing also was met with great results for a very large panel like this. There was a bit of drift in the bottom right of this display, though normal tolerances still showed as passing. All-in, again, for a large 40-inch panel like the UltraSharp 40, this is a solid uniformity result.  


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Dell's UltraSharp 40 U4025QW Performs Admirably With Wide Viewing Angles

Viewing angle performance with this monitor was also excellent. Dell claims a 178° vertical and 178° horizontal viewing angle spec, and we were able to prove that out. Note above how the tiger maintained an abundance of color saturation and contrast. Even black levels remained deep from this angle. This is another key advantage of IPS Black panel technology, and the massive screen real estate and wide viewing angles of the Dell UltraSharp 40 U4025QW highlight this in spades. 

Dell UltraSharp 40 U4025QW Content Creation And Productivity Performance

dell ultrasharp 40 curved workflow example
High Resolution Screen Real Estate For Days

Now that we've gotten past the clinical testing of this big, bodacious display, we'll cover our experiential impressions in a couple of different use cases. Above you can see what you can do with a 40-inch, 5K 120Hz curved monitor, which is to say just about anything. Here we've fired up Power Director for video editing, Adobe Photoshop for photo editing, Discord for real-time chat and a Chrome web browser session with HotHardware.com. This is a good illustration of a content creation workflow on the Dell UltraSharp 40 that is possible with a 40-inch desktop at a super-high 5120x2160 resolution. If you work in a similar flow to this, you'll quickly be spoiled with this kind of precision, screen real estate and top-notch color accuracy. 

Dell UltraSharp 40 U4025QW Gaming And Media Consumption Performance

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Driving 5K Native Res Gaming Will Take Some Muscle

Gaming on the Dell UltraSharp 40 U4025QW monitor has it's pros and cons, however. There's little question that a massive 5K display like this is a heck of a lot of fun to game on, but your graphics card better be up to the task if you're going to game at native res. Here we're driving Indian Jones and The Great Circle at 5120x2160 with the Ultra quality preset and ray tracing enabled. Our GeForce RTX 4090 was breaking a hard sweat, though we still managed a smooth ~60 FPS, which was more than satisfying and a real treat at this panel size and resolution.

If you need to scale things back to 4K or 1440p, however, in order to hit a playable frame rate on a lesser graphics card, the Dell UltraSharp 40 scales down fairly well. It's still a tall order, and don't expect pristine clarity but it gets the job done. Scaling back to 4K is crisp, though 1440p definitely gets a little muddy as does 1080p. For some gamers, the bigger issue with the UltraSharp 40 is that, though it's a 120Hz panel, it has a relatively pokey best response time of 5ms on its Fast setting. In our experience we didn't see a ton of ghosting during game play, though it was observable at times. It wasn't a show-stopper for us by any means but, for those who key on fast response times, or competitive gamers who live or die between the milliseconds, you'll probably want to look elsewhere. This a professional, very accurate, BIG workstation display first, though it does have some game at 120Hz. 

We'll also note that gamers will appreciate the sharp contrast and deep blacks of this display as well. Everything just pops better on this panel, much like you experience with OLED. In comparison to another an LG UltraGear 38 Inch Ultra Wide 1440p Nano IPS panel we had on hand, there was no comparison in terms of color reproduction, though the UltraGear is a 1ms panel specifically targeted for gaming.

Finally, video and movie watching on the UltraSharp 40 was a joy. This panel is up to the task with HDR support, and fast moving action was smooth and ghost free from our experience. In addition, Dell claims the UltraSharp 40's IPS Black panel is also certified for TUV Rheinland 5-Star Eye Comfort levels, and "reduces harmful blue light emissions to ≤35%, compared to ≤50% from its previous generation, for all-day eye comfort without sacrificing color accuracy." So in short, it will help to not disturb your circadian rhythms as well. If you'd like to video stream on the UltraSharp 40 as backup TV to wind down at the end of a day, this 40-inch curvaceous beauty with its 21:9 aspect ratio has you covered there too. 

Dell UltraSharp 40 U4025QW IPS Black Monitor Final Review Analysis

The last main testing and analysis section above really tells you all you need to know about the Dell UltraSharp 40 Curved Thunderbolt Hub Monitor U4025QW (please Dell, let's simplify these model numbers!).  This is a content creation professional's or productivity worker's powerful tool, and a window to massive screen real estate and multitasking, first. If you don't have the need for this kind of high resolution, high fidelity, large display area, there are plenty of other options out there. However, if color fidelity, and a massive high resolution desktop, or multiple desktops are what you crave or need, you can't go wrong with this IPS Black monitor from Dell.  

dell U4025QW Lifestyle
Find Dell's UltraSharp 40 U4025QW Curved IPS Black Monitor At Amazon

Throughout our testing, what was most prominent for us was how rich and vibrant color reproduction is with the UltraSharp 40, with deep blacks and fantastic contrast. Once you get this monitor dialed in with proper calibration, the benefits of IPS Black technology are more than prominent. This display technology is an excellent alternative to OLED panels, and Dell has configured a 40-inch curved 5K HDR Cadillac of a monitor with the UltraSharp 40 U4025QW. At $1489 currently on Amazon, it's a bit of reach price-wise for some, but we think it's a still a strong value for what Dell delivers. Though it has its caveats for gamers, this is one of the best large format monitors we've ever set eyes on, and we can't stop gawking at it, so much so that we're giving it an Editor's Choice award.  
HotHardware Editor's Choice Award

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