My wireless network connection is dropping out and its driving me nuts. It is weird because it happens at totally random intervals and other devices work while my computer has been dropped. Both my USB dongle and wifi card randomly disconnect from the router and I am unable to connect for a couple of minutes. It is especially irritating because two different adapters are failing at the same time, sounds like a software problem to me, but where? Both my laptop and iPod remain connected when the connection drops. What on earth is happening? I doubt its the router because the other devices would disconnect as well.
I agree with you that it is most likely not an issue where the router is dropping the connection, and I agree for the same reasons... you would see ALL of your wireless devices drop. Now... when you say drop... you mean that the wireless connection is broken AND it is not automatically reinstated. I make that distinction simply because the iPod and the laptop could also be dropped, but they could re-establish their connections, and you might not notice this.
Is the environment an issue? As has been pointed out, cordless phones that operate at 2.4ghz will interfere with a 2.4ghz based wireless router. Soft materials like drywall, wood, furniture, etc.. will ALSO interfere with wireless signal strength. Large amounts of metal between you and the router will ALSO interfere with wireless signal strength. Maybe just making yourself a shield for the antenna on the router from Free Antennas and boosting the signal strength will take care of the issue.
It could be the channel your router is operating on, if it is at odds with a neighbor's wireless router. This could happen if the computer that is using the wireless devices that are dropping is closer to a neighbor's home than the devices that are NOT dropping.
Here is what I propose you do. Log into your router. Change the broadcast channel (don't use 1 or 6 or 11 as they are the standard channels most widely used). If you are using the default SSID (name) like "linksys" or "default" or "netgear" or "belkin54g", change that to something unique. This will cut down on people unintentionally attempting to access your router. Make sure that you are using wireless security, but step down on the type. If you are using WPA2, step back to WPA. If you are using WPA, step back to WEP. If you are using WEP 128bit, step back to 40bit. Why? The higher the level of security, the better the quality of connection you need to connect and STAY connected. Thus, you can connect reliably and constantly with a 40bit WEP secured connection where you might only be able to connect sporadically with a WPA2 connection.
In short, I would stick a pin in the RESET hole in the back of your router, hold it for 10 seconds, and then set it up all over again, from the ground up. New name, new channel, and base line level of security. Why? Because that is MUCH easier than reinstalling your Operating System... which is one of the possibilities.
If none of this works, and you feel like there is now something wrong with the install of Windows on your computer... you could be right. So... try removing the OS from the equation. It is potentially easier than it sounds. For one, you could download Linux Mint and boot to the LiveCD. It is a version of Linux with excellent hardware compatibility from the get-go. You wouldn't have to install it. It should work with your existing wireless hardware from the LiveCD. If you boot to the disc, and it DOES detect and want to use your wireless card, GREAT! Now, just use the LiveCD OS for a little while, and see if your connection drops. If your connection does NOT drop, then you know it is not a hardware or environmental issue... since just removing your install of Windows from the situation actually fixed the situation.
Since you are talking about two different wireless cards (installed and USB) that disconnect at the same time, you can't really just uninstall and reinstall the drivers for them. If using the LiveCD shows that the problem is software, you are then facing a reinstall of Windows. But knowing how Windows works, and what most people face... reinstalling Windows fresh isn't really a bad idea on occasion.