Iiyama G-Master GCB4580DQSN-B1 review: an enormous ultrawide monitor with appealing features

Is there such a thing as too big when it comes to monitors? The days of using Quark Xpress on 17-inch CRTs may be behind us, but surely there's no need for anything bigger than those 20in Sony Trinitrons that were popular around the turn of the millennium. Iiyama begs to differ, with a 45-inch ultrawide screen that’s going to make you wonder if you need a bigger desk, perhaps even a bigger building, to house it.

Iiyama G-Master GCB4580DQSN-B1 review: key specifications

Iiyama G-Master GCB4580DQSN-B1 review: Design and build

The GCB4580DQSN-B1 has a 1500R curve, which means the edges wrap around your peripheral vision and make it easier to position yourself for optimum viewing. You don’t want to be too far away, but sitting too close means having to move your head. Despite having a diagonal measurement of 45 inches (114cm), the screen is only 34cm tall - the same as a 24-inch 16:9 monitor (with a slightly thicker bezel) - so this isn’t ideal for working with lots of documents that need to be viewed in portrait orientation. Or indeed landscape, as the distance between the two sides is just too vast.

Essentially, a monitor like this acts like two 1440p screens with no gap in between, and this makes it ideal for tiling application windows or playing certain first-person games with extra immersion - though support for the ultrawide resolution needs to be baked into the game itself. Being able to have a text document, a browser window, a chat app and something like Photoshop all tiled neatly across the expanse of screen, however, makes for a powerful way to work, with no need to arrange your windows so they’re not across the join. It also means there's only one stand on your desk (there’s a VESA mount on the back of the GCB4580DQSN-B1, but it’s the less common 200x100mm size) and only one cable feeding the video signal.

Iiyama G-Master GCB4580DQSN-B1 review: features

Behind the enormous screen, you’ll find a row of inputs, all conveniently labelled for ease of finding. The most interesting is the USB-C, which delivers 90W of power to your laptop and means you can connect it via a single cable if it has the appropriate port itself (Thunderbolt, most likely).

You’ll find two HDMIs, a single DisplayPort, and the USB and Ethernet ports comprising its useful KVM and hub. You can switch between two computers, one connected by USB-C and the other by USB and a video port, allowing you to swap between a gaming PC and a MacBook, for example. The Ethernet port is a nice touch, enabling high-speed network capability to be shared.

The supplied stand allows 130mm of height adjustment, a 20° tilt, and a degree of rotation, though this isn’t a screen you’ll want to use in portrait orientation - it’s useful for accessing the ports at the back though.

Iiyama G-Master GCB4580DQSN-B1 review: performance

The GCB4580DQSN-B1 uses a VA panel, a display technology noted for its high contrast and wide colour response that’s often used by TV manufacturers who haven’t made the jump to OLED. Here, it shows off the technology’s switching speed with a maximum refresh rate of 165Hz. The screen’s claimed maximum brightness is 450 nits, and while that may be true for HDR content, we found that in everyday use 378 was about as high as it would go.

The screen displays 100% of the sRGB gamut, 81% of Adobe RGB and 88% of P3. The resolution of 5120 x 1440 works out to 7.4 million pixels, still fewer than a 4K screen, and a further resolution limit is imposed by the fact you probably won’t be using all those pixels at once, as you might on a regular widescreen monitor.

This aside, sitting back and enjoying both the way an ultrawide monitor like this improves your daily work life, if you’re in the habit of having multiple applications open at the same time, and also just how cool it looks on your desk,

Iiyama G-Master GCB4580DQSN-B1 review: price

The £800 asking price for the GCB4580DQSN-B1 looks pretty reasonable alongside the LG Ultragear 49GR85DC and Samsung Neo G9, both of which are in the region of £400 more for a 49-inch screen. Iiyama’s 45-incher is naturally more expensive than the multiple 34-inch options, including Iiama's own GCB3480WQSU-B1 which can be had for less than £400.

Iiyama G-Master GCB4580DQSN-B1 review: who is it for?

You’ll need a big desk and a need for multiple, moderate-resolution windows to consider the big Iiyama. It has applications in gaming, of course, and if you’re partial to a bit of Baldur’s Gate 3 or Horizon: Zero Dawn (both of which support ultrawide resolutions) then having a games PC or console plugged in alongside your MacBook can be a very enjoyable way to spend time with a screen like this. A single ultrawide isn’t necessarily better than two separate widescreen monitors, as the flexibility to rotate screens and view multiple sources at the same time may be important, but if you think it will work for you, then being able to surround yourself with a screen in the way a large curved ultrawide can is a great way to work.

Should I buy the Iiyama G-Master GCB4580DQSN-B1?

Buy it if:

• You want a big screen
• You have plenty of space
• You don’t mind the curve

Don’t buy it if:

• You’d rather have two monitors
• You want picture-in-picture
• You don’t have a big enough desk

Also consider

HP Z34c G3
This 34in ultrawide has good colour accuracy, but only a 60Hz maximum refresh rate.

Iiyama G-MASTER GCB3480WQSU-B1
Essentially a smaller version of the 45-incher here, it’s cheaper but has less resolution.

Dell UltraSharp U4924DW
A ludicrous 49 inches across the diagonal, the Dell is bigger but slightly less bright.