Q: My iMac (purchased Feb 6) is constantly dropping the wifi signal. It seems to happen randomly...sometimes it's there, sometimes not.  Have tried everything I know.  Just discovered thread here in which many others are complaining of the same issue.

There are many people complaining, but there are many potential reasons.

First make sure you have everything up to date by running Software Update, and make sure your wireless router has the latest firmware.

Wireless interference can certainly cause the problems you describe. Your iMac (and the iPad 2) can use 802.11n and 5 GHz channels. This is the best way to minimize potential sources of interference. Make sure your router is using it.

(My iPad2 and IPhone are not having this problem...or perhaps their 3G has kept me from noticing.)

That is possible. To isolate the problem to your iMac, you would need to compare its performance to a comparable WiFi client.

Kelly, first off you haven't made a big mistake, I promise you! Is the router in the same room as the iMac? Have you considered connecting the iMac to the router with an ethernet cable? It would solve all of the wireless issues, and if you really don't need wireless o. The imac......ya know?

Here's a whole page of things to look at that may help you.

http://support.apple.com/kb/HT1714?viewlocale=en_US