Cordless Mouse & Keyboard Lag

No. But some cordless mice are also optical. The refresh rate of the optics will give some lag which may be annoy during rapid movements of the mouse.
I use the logitech dual optical. It has a faster refresh rate and larger resolution. Its great for gaming and I've never noticed any lag. But it doesn't come in a cordless version due to the extra power consumption of two leds.

<i><b>Engineering is the fine art of making what you want from things you can get</b></i>
<A HREF="http://www.btvillarin.com/phpBB/viewtopic.php?t=655" target="_new">My systems</A>

I have read the cordless versions have lag too not just because the optics, at least this what I heard in some of the gaming magazines.

the Prisoner

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To straighten it out a bit. Optical cordless mice needs batteries to function. So to reduce the power consumption of the device, all sorts of tricks are made. E.g. the led in optics is flashing at a high frequency since that improves its efficiency. This frequency is what I refer to above as the refresh rate of the optics. Now there is really no point in transmitting anything to the PC faster than that.
However, if the mice has a cord, the refresh rate of the optics can be increased without worrying about power consumption.
IMO it would be an extreme poor design to have smaller refresh rate on the cordless comunication than on the optics.
So PooBaa are you sure about this. I think Im going to measure it on my friends optical/cordless mice.

<i><b>Engineering is the fine art of making what you want from things you can get</b></i>
<A HREF="http://www.btvillarin.com/phpBB/viewtopic.php?t=655" target="_new">My systems</A>

I just got one of these a couple of days ago. It's real nice. However, I do notice a bit of lag during gaming which I don't seem to have with my mechanical cordless mouse (which is also a Logitech). So, I use my cordless, rechargable, optical mouse for everything but gaming. Dual mice!

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I have been using an Intellimouse Explorer for a few years now. I tried switching to the wireless version but I couldn't stand the wireless lag... it is definitely there... and it is definitely noticable if you use your computer a lot with a good mouse. Not too mention that the thing eats batteries a lot more than i expected... changing at the very least once a month... sometimes twice.

needless to say, I"m back to my original intellimouse explorer. I have used this thing for so long and so much that it has erosion on the plastic from my fingers. Works just the way it did when it was brand new... I just can't bear to buy another one... the new explorer design is much worse than these older ones... atleast IMO.

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look at websites that specialize in colorful cases, they usually have a variety in their keyboards so people can match them to their cases. Unfortunatly that usually means shelling out a few extra bucks.