intermittent connection D-Link

I've got D-link DML 640+ router with a Di 520+ card and just yesterday it started dropping the connection...repeatedly. I get a error notice saying the connection can't be found, then it finds it and pops up a window asking me which connection I want to connect to, although it has a box to check saying it's an unsecured connection(i'm not using WEP or any security settings), which I check, but then it still refuses to connect. For a while it would connect for a minute or two then drop the connection, now it pretty much refuses to connect at all. The situation had gotten steadily worse for the past two days. I know it's not the router because I'm sitting here next to the computer in question with my laptop w/ DWL 650+ card and running just fine. I reinstalled drivers and went throught the advanced settings configuration with the laptop and matched the settings. No result. Time to replace the card?
Good card gone bad? Any suggestions?

EDIT: It's wireless set up I'm discussing.

Have you tried a different cable?
Rob

I guess I should've specified that it is a wireless set up. But there is a computer hooked up hard wired and it works great, and my laptop is set up wireless and it works fine.

FYI, picked up a replacement card in town this afternoon and have stayed connected for 15- 20 minutes without a hiccup. Must be a popular card, sold out at the one establishment and got the last one on the shelf at the other. Will keep you posted. Plus showing a stronger signal than the other ever did.

So it was the card. I'm glad you got it fixed.
Rob

I think the original card was defective from the get go. This one is running over twice the signal strength the first one ever had. D-Link has a three year warranty so I should even regroup the cost. Thanks for the input.