Picture-in-Picture and Picture-by-Picture on a 21:9 Monitor Explained

A 21:9 panel has enough spare width that splitting it between two sources is genuinely practical, not just technically possible. Picture-in-Picture and Picture-by-Picture are the two ways a monitor can do that split, and they solve noticeably different problems once you know which is which.

Quick Answer

PiP drops a second input into a small floating window layered over your main source, suited to monitoring something without dedicating real space to it. PbP instead splits the panel into two independent live halves, giving each source its own genuinely usable area. On a 3440x1440 screen, a PbP split gives each half roughly 1720 pixels of width, considerably more room per source than the same split would offer on a standard-shaped monitor. Both modes vary by model, so dig into whatever Input or PIP/PBP section the on-screen menu of your R5,999 CU34B3E or any other unit offers to see what it actually supports.

🖼️ When PiP is the right choice

PiP suits a specific kind of task: keeping an eye on something without giving it any meaningful screen real estate.

A small overlay window, typically occupying somewhere around 15% of the screen in a corner and often resizable through the monitor's menu, shows a second source while your primary content fills the rest of the screen normally. This suits watching a security feed, monitoring a background process on a second machine, or keeping a video call visible while working elsewhere on the panel, none of which require reading fine detail continuously from the secondary source.

⬛ When PbP is the right choice

PbP suits a genuinely different need: actually working within both sources, not just glancing at one occasionally.

Splitting the panel into two regions, commonly left and right, gives each source real working width rather than a small overlay. On a 3440-pixel-wide screen, that split still leaves roughly 1720 pixels per side, which is close to the full width of a standard monitor, meaning each half remains genuinely usable for reading documents, comparing outputs from two machines, or running two applications that both need real screen space.

🔍 Checking what your specific monitor actually supports

Neither mode is guaranteed on every monitor, and the details of how each works vary meaningfully between models.

Support for PiP and PbP depends on the video processing hardware built into a specific panel, and not every model offers both, or offers them with the same input combinations and resolution limits. Some monitors restrict resolution or refresh rate while either mode is active, and some limit which input types, such as HDMI paired with DisplayPort, can be combined. The fastest way past all of this guesswork is hands-on: wire up both devices, open the on-screen display, and see for yourself what toggles on without breaking anything else.

The office monitor range and the general monitor category cover other panel choices, while a KVM switch from monitor accessories is worth a look if neither PiP nor PbP ends up suiting your two-source routine.

Frequently Asked Questions

Which mode is better for keeping an eye on a video call while working?

PiP, since it keeps the call visible in a small window without taking meaningful space away from your primary task.

Which mode gives more usable space per source?

PbP, since it splits the panel into two genuinely usable regions rather than layering a small window over the main content.

Does every 21:9 monitor support both PiP and PbP?

No. Support depends on the specific monitor's video processing hardware and varies by model, so test it directly through the on-screen menu rather than assuming.

Can I use PiP and PbP with any combination of input types?

Not always. Some monitors restrict which input combinations, such as HDMI with DisplayPort, can be used together in either mode, which the on-screen menu will confirm the moment you try enabling it.

Does using PbP reduce the resolution available to each source?

On some monitors, yes, since resolution or refresh rate can be limited while either mode is active, which shows up immediately in the display settings on whichever machine is connected to that side.