Atheros Wireless card problem - really bizarre

Hi all, I'm new to the forums and apologies that my first post is a cry for help - but I am close to throwing my laptop out the window with this one!

Here's the deal: I have an ASUS F3 series laptop running Vista with an Atheros AR5BXB61 internal wireless card. My router is a Sweex LW055 and it's attached to my 10mbit cable internet. The problem is this - my wireless card randomly disconnects from the router, and seems to just deactivate. If I try to reconnect it can't find any networks, and the only way I can find them again is if I put my laptop into hibernate mode and bring it back up again (or reboot, but hibernate is quicker). It doesn't work if I disable and then enable it again in Control Panel. It doesn't work if I switch the wireless console button off and on again. The only way I can reconnect is by powering my machine down. I have the card's power saving settings to 'Always on', and I'm just at a loss as to why this is happening

This problem has happened ever since I got the laptop, and even when the motherboard fried earlier this year and I got it replaced - it's been doing it since I got the new one too. It happens completely at random, sometimes I can be steadily connected for hours and other times it will cut me off after 2 minutes... I am climbing the walls and would really appreciate some help!

Incidentally the router is fine - my girlfriend also has a laptop (Acer, the type I wish I'd bought!) with an internal wireless card and hers has no problems connecting, ever.

To compound things - I got a USB dongle with the router but when I try to use that to connect it doesn't accept the network password despite the fact I know it's the right one!

I've been having the same problem for the last few months. I think that Atheros is a low end card and nowhere near as good as Intel. I would get a new card if I were you. I would if HP didn't lock you into using their own $500 "FCC Approved" (bullshit) Intel cards.