One cool thing in Penumbra: Requiem is that you can really use Full HD resolution! (1920x1080)
How many games uses Full HD? This is the only game that I know...
I don't believe computer monitors really can support real HD at all. As far as I know, the standard computer monitors isn't even in the right size to support any kind of HD. It's only a marketing trick.
There are a lot of game that uses these higher resolution. Most games check resolutions supported by your monitor during startup. Then, the bigger monitor you've got, the more resolution to choose from.
I think the later CS games can use HD, we set it up to a huge plasma and played once
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