How do I remove the limit on PC keyboard button presses?

  • Whenever I play a PC game with the directional keys, I can only press two buttons at a time. For instance if I am playing a shooter like R-Type, I cannot hold down the fire button while moving diagonally at the same time. The computer simply ignores the extra button press.

    How do I remove this limit so I can shoot while moving diagonally? This limitation seems to apply for every game.

    I am running Windows 7 if it makes any difference. I noticed the same problem back when I used Windows XP.

  • This is a hardware limitation of your keyboard. Unfortunately, the only solution is that you must purchase a better keyboard that does not have this limitation.

    To be more specific:

    In order to save money, keyboard manufacturers often put many keys on the same "circuit" of sorts within the wiring of the keyboard. This prevents multiple keys in the same region of the keyboard from being pressed simultaneously. Sometimes it even prevents more than 2 keys at all from across the whole keyboard being pressed at once. Often the shift, ctrl, and alt keys are not within this limitation, so you can hold shift and press 2 other keys at once and it will still work fine.

    Even high-end gaming keyboards often have a similar hardware limitation, although the cap is much higher so that it is unlikely to be reached during the normal course of gaming.

    This is a common limitation of laptop keyboards, especially.

    Any suggestions on how to identify this when purchasing keyboards?

    Mechanical switch keyboards usually allow multiple presses but can be rather expensive

    Raven > This may sound juvenile, but if you're physically purchasing your keyboard(s) at a store, as opposed to buying online, you could always ask to try it out on a PC, and see how many keys you can press at once. That's what I usually do, and most retailers won't mind. If the retailer doesn't have a computer handy, you could bring a laptop.

    Notably, Das Keyboard allows 6 keys simultaneously on USB and any number of them on PS/2.

    @Raven: The term you're looking for is called "Rollover". Most cheaper keyboards are 2KRO (2-key rollover), meaning any two keys can be held down at once and still be detected *(though most of them have 3- or 4-key rollover for **most** of the common key-combinations for games, like keys near W-A-S-D)*. The maximum possible through USB is 6KRO. Through PS/2 port there is no limit; keyboards which support any number of simultaneous keypresses are called NKRO (n-key rollover). Check the specs when buying a keyboard to find out its rollover.

    @Raven: Also, MS and logitech sometimes market keyboards as "anti-ghosting." This is a marketing term for "better than 2KRO," though often it just means 3KRO. Again, check the keyboard specs *(either on the box, or on amazon/newegg)* to find out the exact rollover.

    It's surprising and interesting that that's a limitation of USB as used by modern keyboards. Why, though?

    @Mussri The limitation can be overcome with modern USB keyboards. Mine supports NKRO, but it may have something to do with using 2 USB ports.

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Content dated before 6/26/2020 9:53 AM