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Lets talk "IRQ"'s.  I noticed in one of my servers a video card and USB both have the same one.

Medium Priority
Last Modified: 2012-05-06
They both show IRQ 7 in the bios.  How can they both use the same one?  Can I add more IRQ's?  What exactly are IRQ's?
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This comes from the *old* days of DOS.  IRQ's allowed a hardward device to interact with the computer thru something called an "Interuppt Request Level"  hence the IRQ.

Again , in the old days, you used to have to manually set devices to use a specific IRQ , such as a com port, LPT port, or a modem or such.  They were not shareable; but now devices play together much nicer...

Hope that helps

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Back in the day (DOS) Com1&Com3; Com2&Com4 shared a common IRQ; however both devices could not communicate at the same time. IRQs are hardware lines used to communicate with the processor. SImply, the hardway shoots "hey, got something" to the processor.

Modern OS's have worked around the problem (its been years since I had OS Theory classes at this level)... so please don't ask me to explain.

If you are using DOS - it'll likely be a problem, XP, Vista, etc -- you should be OK.

Can't add IRQs.

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