How do I fix an intermittent wireless connection?

I have a Cyberpower PC Q8200 with WinXP (Intel Core 2 Quad CPU). It has connected to the wireless network in my house just fine, until I moved the box to another room.

I also have a laptop (using now) in the same location, which has no trouble connecting to the wireless network.

Since I physically re-located the desktop, it usually can't find the wireless network, or it finds it with a very low signal and then loses it again. I suspect that maybe the network card is loose from the move.

I haven't done a lot of hardware at all. Where is the wireless network card, and how might I check to make sure it is not loose?

I loose card would sometimes not show up in the hardware info and could crash your workstation. If it's getting a week signal it's more likely that your antenna is loose or not oriented correctly. If your antenna unscrews, try taking it off and reattaching it. Also try adjusting it to be parallel to the antenna in the base station. The PC and base station antennas should look like this | | or this / / not this / \. (YMMV)