OP or anybody else wondering: avoid using the term '2K', because it is lazy and often used incorrectly by people who fail at maths. And manufacturers who spread this incorrect rubbish. There was no such things as '2K' as a term before '4K' came along. The 'K' refers to a
slightly rounded up version of the horizontal component of resolution:
- 3840 x 2160 is generally referred to as '4K' (or more correctly UHD) because 3840 is close to '4K'.
- 1920 x 1080 has half the horizontal (and vertical) resolution components, so by the logic used above for '4K'
this is actually '2K'.
- 2560 x 1440 should be referred to as '2.5K' if anything, although it is commonly (misleadingly) referred to as '2K'.
And yes, as James Miller said above, the use of 'P' is entirely redundant. It is something that should really have been confined to old TVs, certainly not used to describe a monitor only resolution of 2560 x 1440. '1440p' indeed
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