Yes, you can rotate the Samsung Odyssey G4 vertically. The monitor has a rotation function that allows you to switch it to portrait mode.

Do you mean on a Playstation or something? No problem...

Included in the box when you buy it, or you can see it on the supplier's website as a spare part

The HDMI cable supplied with the Samsung Odyssey G4 - G40B monitor (LS27BG400EUXEN) supports HDMI 2.0. This is indicated by the product specification, which mentions the use of HDMI 2.0 for video connections.

The monitor supports HDMI 2.0. HDMI is downward compatible so yes, it is compatible.

The Odyssey G4 - G40B monitor from Samsung has a DisplayPort version 1.2 connection.

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Yes, the screen has no speakers.

No, this is not normal. If the screen and computer settings are correct, my Odyssey displays very good quality.

I received a Swiss power plug but no DP cable was included.

Of course, you'll need a vesa 100x100 support.

yes, with a 100x100mm VESA plate

You can connect speakers via the 3.5mm jack on the screen. You can find compatible speakers by filtering "audio connection" jack 3.5mm in the speakers section.

This is both wrong, it is a 25 inch monitor. The exact designation with the article number is: 25" Odyssey FHD Gaming Monitor G40B. However, if you want a monitor that can also be used for word processing and internet, I wouldn't use it. For less than 300 francs, there are already very good 4K UHD screens that offer 4 times the resolution of 3840 x 2160 pixels. Texts are reproduced with pin-sharp clarity.