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Comment by alasdair_ | Hacker News Reader

Isn't a big part of the reason "gaming" keyboards cost so much because they can register more than three keys (sometimes four) being hit at the same time - something many cheaper keyboards cannot do due to the way they are wired?

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This is known as key rollover, see: https://en.wikipedia.org/wiki/Rollover_(key)

It is a result of the matrix wiring of the keys, though more expensive keyboards will have them wired individually, mitigating this issue.

Yes, n-key rollover sometimes comes up. In practice, I've only had it become an issue in the wild either when more than one player is sharing the keyboard or, in some rare games, primarily simulators, where you might need to hold multiple keys.

It's a frequent issue in FPS games. Simultaneously pressing four keys isn't particularly unusual in an FPS, but it confounds an awful lot of non-gaming keyboards.

I've had keyboards which where marketed as professional keyboards have very obvious problems with this. Specifically, I had a Logitech MX5500 and if you where holding down the 'D' key and then pressed the 'S' key, the keyboard would never send the 'S' key (though I might remember those keys backwards). This is a problem because many a video game has you use the 'WASD' keys as direction keys to control movement, so trying to move backwards and to the right would fail.

So it's not like nobody experiences this problem.

As mentioned in my other comment, that is a symptom of ghosting, not of being limited to the standard 6-key rollover set by the usb spec.

ghosting can also cause issues with holding multiple keys at once and is more likely what they are referring to. Details here: https://www.microsoft.com/appliedsciences/antighostingexplai...

If you hold C for crouching, you can't move on some diagonals and switch weapons at the same time. Many games/gamers use shift or ctrl now for crouch to work around that.

You might be thinking of ghosting as opposed to n-key rollover. Of course keyboards that address one tend to address the other as well, but still, small distinction.

That said.. how are you holding C to crouch? I assume for WASD movement. I just tried that and it's contorting my hand in weird and uncomfortable ways.

No the OP, but I used do the same thing.

I shifted my hand to the right so that my middle finger is on D, my ring finger moved forward and back (WS), and pinky for A.

That evolved from gaming on a laptop where I'd just rock my index finger back to hit C or shift my thumb forward and rock back on the space bar to jump. I got disturbingly good at Q3Arena on a Powerbook G3, yes, using the track pad. It inspired some bad ergonomic habits. haha

Now I just use Ctrl.

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