Internet Extremely Slow

I have an Rev A iMac G5. I recently took it in to Apple for repair. The logic board and capacitators were replaced. My internet connection has been extremely slow for the past few days. I use Airport to connect wirelessly. I've cleaned the cache, etc. but it doesn't seem to help. I even took the Airport card out and put it back in. I don't think it's anything related to my router because my MacBook can connect and load everything just fine. What else should I do?
Rev A iMac G5, white MacBook 1.83 Ghz Mac OS X (10.4.7) iPod 3G, iPod nano, Kodak V550 camera
Rev A iMac G5, white MacBook 1.83 Ghz   Mac OS X (10.4.7)   iPod 3G, iPod nano, Kodak V550 camera

"I use Airport to connect wirelessly."
Suggest that you also crosspost over in one of the AirPort Forums where the Airport users hang out so that they can also see your question.
This way you can kill 2 birds w/one stone & probably get more responses.

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