Slow Wi-Fi, and Complete system lock ups?
We had a Dell Inspiron 300 Series that kept crashing. After a certain amount of time the screen would completely lock up, and the only way to fix this was to shut down the laptop with the power button.
When started in Safe boot the system would not freeze up so it seemed like possible software problem. But after some trial and error the problem seemed to be with the wireless card. I removed the wireless card and the laptop ran good for more than a week.
After this I tried updating all the drivers for the Wireless device but did not seem to help.
After This I contacted dell and they send a new Wireless card. And after testing this card for more than a week I can happily say that there are no more crashes.
I am not sure this is a problem with a certain batch of wireless cards but at least this fixed it for me.