Changed Video Card And No Online Cod4

I have been reading this forum for a couple of weeks now and cannot find my problem or a resolution.

My 8800gt needed repair and I was using my 7900gt when I installed Windows 7 rc.

COD4 was working fine with the 7900gt, a little screen lag but no connection interrupts.

When I got my 8800gt back, I installed it with the same video drivers.

I entered an online server, it loads, I select side, weapons, and then I get a connection interrupt immediately.

I have tried updating video drivers to 190.56, with the same connection interrupt resulting.

I can play single player all day long without a problem.

I installed WAW, single player plays great, but the exact same result in multiplayer games.

I have tried running from the disk, as administrator, compatibility mode, punkbuster on and off, and with and without xfire.

Nothing changed, connection interrupt as soon as the map comes up.

My broadband is from a wireless isp, it is 1meg down and 1/2 meg up.

Not great but all I can get and has worked fine in the past.

I usually play on Chicago servers with a ping less than 100ms.

I have also tried disabling the firewall, and allowing cod4 and waw.

Nothing helps.

So it must be Windows 7 or might my isp be blocking game servers some way?

I got Farcry2 to entertain myself while getting this figured out and the single player works good.

I have not registered with ubisoft to try it online, my next step.

But I find ubisoft a bit intrusive and really like cod4 more.

Any ideas or advice would be greatly appreciated.